×

The lacertid lizard Gallotia galloti inhabits drastically different environments on the island of Tenerife, from sea level to > 3500 m, encompassing mesic as well as extremely arid sites. To obtain a first exploratory overview of the thermophysiology of lizards in this range of environments, we experimentally inferred preferred temperature (Tpref) and instant evaporative water loss (IWL) in 63 individuals from five bioclimatically distinct sites. We found statistically significant but weak differences between individual median Tpref values across sites, without an obvious relationship to bioclimate. Considering only adult male lizards, the highest Tpref values were found at one mesic and one very arid site. IWL differences were also significantly different across sites, and this variable was positively correlated with rainfall if analysed at the level of individual lizards, a hypothesis that requires testing against more extensive data sets. It appears that G. galloti occupies an extensive range of bioclimates without heavily adjusting its thermal physiology to local conditions.

×

Spontaneous regrowth of the axons of retinal ganglion cells (RGC) occurs after unilateral optic nerve transection (ONT) in the lizard Gallotia galloti. We have performed an immunohistochemical and ultrastructural study of the conus papillaris (CP) of this lizard during ontogeny and after ONT in order to characterize its cell subpopulations, innervation and putative blood-brain barrier (BBB) and to evaluate changes occurring throughout regeneration. Proliferating PCNA+ cells were abundant between embryonic stage 33 (E33) and hatching. From E33, we observed Pax2+/GS+ glial cells in the primitive CP, which became increasingly pigmented and vascularised from E35. Conal astrocytes coexpressing Pax2 with vimentin and/or GFAP were identified from E37-E38. GluT-1+/LEA+/Pax2- endothelial cells (ECs) formed a continuous endothelium with tight junctions and luminal and abluminal microfolds. In adults, the peripheral blood vessels showed a thinner calibre, stronger GluT-1 staining and more abundant microfolds than those of the central CP indicating the higher specialization involved during transport within the former. Occasional pericytes, abundant Pax2+ pigment cells, LEA+ microglia/macrophages, unmyelinated Tuj1+ nerve fibres and SV2+ synaptic vesicles were also observed in the perivascular zone. After ONT, the expression of GluT-1 and p75NTR persisted in ECs, suggesting the preservation/early recovery of the BBB. Relevant ultrastructural alterations were observed at 0.5 months postlesion, although, by 3 months, the CP had recovered the ultrastructure of controls indicating tissue recovery. Abnormal newly formed blood vessels had developed in the CP-optic nerve junction. Thus, the CP is a central nervous system structure whose regenerating capacity might be key for the nutritional support of regenerating RGCs in G. galloti.

×

Identifying the factors generating ecomorphological diversity within species can provide a window into the nascent stages of ecological radiation. Sexual dimorphism is an obvious axis of intraspecific morphological diversity that could affect how environmental variation leads to ecological divergence among populations. In this paper we test for sex-specific responses in how environmental variation generates phenotypic diversity within species, using the generalist lizard Gallotia galloti on Tenerife (Canary Islands). We evaluate two hypotheses: the first proposes that different environments have different phenotypic optima, leading to shifts in the positions of populations in morphospace between environments; the second posits that the strength of trait-filtering differs between environments, predicting changes in the volume of morphospace occupied by populations in different environments. We found that intraspecific morphological diversity, provided it is adaptive, arises from both shifts in populations’ position in morphospace and differences in the strength of environmental filtering among environments, especially at high elevations. However, effects were found only in males; morphological diversity of females responded little to environmental variation. These results within G. galloti suggest natural selection is not the sole source of phenotypic diversity across environments, but rather that variation in the strength of, or response to, sexual selection may play an important role in generating morphological diversity in environmentally diverse settings. More generally, disparities in trait–environment relationships among males and females also suggest that ignoring sex differences in studies of trait dispersion and clustering may produce misleading inferences.

×

Poikilothermic animals show a strong dependence on environmental temperature. However, they are able to adjust their body temperature through behavioral and partial physiological thermoregulatory adjustments. In this way, they optimize the heat loss and gains to keep the body within a range of thermal preference and to allow maximizing their physiological efficiency. A group of Gallotia galloti lizards were placed in a terrarium with a wide thermal variation in different regions. In this way, the animals were able to select the most thermally comfortable region. However, they should leave this region to get food, which was placed in a cold region, with a temperature far away from the comfort temperature. The time-lapse thermographic cinematography recordings allowed recording the environmental and body temperatures as well as the variations in different parts of the animal body in function to the temperature of the environment. In this way, it was found that the cephalic temperature was maintained within the 33 – 37 range in spite of occasional visits, the coldest spot in the terrarium at 13ºC to get food. Most frequently, the animals preferred to stay in 25-30ºC regions, while maintaining a cephalic temperature of up to 10ºC higher.

×

In the developing brain, the phenomenon of neurogenesis is manifested heterotopically, that is, much the same neurogenetic steps occur at different places with a different timetable. This is due apparently to early molecular regionalization of the neural tube wall in the anteroposterior and dorsoventral dimensions, in a checkerboard pattern of more or less deformed quadrangular histogenetic areas. Their respective fate is apparently specified by a locally specific combination of active/repressed genes known as “molecular profile.” This leads to position-dependent differential control of proliferation, neurogenesis, differentiation, and other aspects, eventually in a heterochronic manner across adjacent areal units with sufficiently different molecular profiles. It is not known how fixed these heterochronic patterns are. We reexamined here comparatively early patterns of forebrain and hindbrain neurogenesis in a lizard (Lacerta gallotia galloti), a bird (the chick), and a mammal (the rat), as demonstrated by activation of acetylcholinesterase (AChE). This is an early marker of postmitotic neurons, which leaves unlabeled the neuroepithelial ventricular cells, so that we can examine cleared wholemounts of the reacted brains to have a birds-eye view of the emergent neuronal pattern at each stage. There is overall heterochrony between the basal and alar plates of the brain, a known fact, but, remarkably, heterochrony occurs even within the precocious basal plate among its final anteroposterior neuromeric subdivisions and their internal microzonal subdivisions. Some neuromeric units or microzones are precocious, while others follow suit without any specific spatial order or gradient; other similar neuromeric units remain retarded in the midst of quite advanced neighbors, though they do produce similar neurogenetic patterns at later stages. It was found that some details of such neuromeric heterochrony are species-specific, possibly related to differential morphogenetic properties. Given the molecular causal underpinning of the updated prosomeric model used here for interpretation, we comment on the close correlation between some genetic patterns and the observed AChE differentiation patterns.

×

Eine Forschungsgruppe der Universitäten La Laguna und Gran Canaria hat entdeckt, dass die kanarische Eidechsenart Gallotia galloti in der Lage ist, den Sehnerv zu reparieren, wenn er beschädigt wird.

×

Algyroides fitzingeri, Algyroides marchi, Algyroides moreoticus, Algyroides nigropunctatus, Lacerta agilis, Lacerta lepida, Lacerta princeps, Lacerta schreiberi, Lacerta strigata, Lacerta trilineata, Lacerta viridis, Lacerta andreanszkyi, Lacerta armeniaca, Lacerta bedriagae, Lacerta brandtii, Lacerta cappadocica, Lacerta caucasica, Lacerta chlorogaster, Lacerta cyanura, Lacerta danfordi, Lacerta derjugini, Lacerta dugesii, Lacerta fraasii, Lacerta graeca, Lacerta horvathi, Lacerta jayakari, Lacerta laevis, Lacerta monticola, Lacerta mosorensis, Lacerta oxycephala, Lacerta parva, Lacerta perspicillata, Lacerta praticola, Lacerta rudis, Lacerta saxicola, Lacerta vivipara, Gallotia atlantica, Gallotia galloti, Gallotia simonyi, Podarcis erhardii, Podarcis filfolensis, Podarcis hispanica, Podarcis lilfordi, Podarcis melisellensis, Podarcis milensis, Podarcis muralis, Podarcis peloponnesiaca, Podarcis pityusensis, Podarcis sicula, Podarcis taurica, Podarcis tiliguerta, Podarcis wagleriana, Psammodromus algirus, Psammodromus blanci, Psammodromus hispanicus, Psammodromus microdactylus.

×

Differences in surface structure (ober- hautchen) of body scales of lacertid lizards involve cell size, shape and surface profile, presence or absence of fine pitting, form of cell margins, and the occurrence of longitudinal ridges and pustular projections. Phylogenetic information indicates that the primitive pattern involved narrow strap-shaped cells, with low posteriorly overlapping edges and relatively smooth surfaces. Deviations from this condition produce a more sculptured surface and have developed many times, although subsequent overt reversals are uncommon. Like variations in scale shape, different patterns of dorsal body microornamentation appear to confer different and conflicting performance advantages. The primitive pattern may reduce friction during locomotion and also enhances dirt shedding, especially in ground-dwelling forms from moist habitats. However, this smooth microornamentation generates shine that may compromise cryptic coloration, especially when scales are large. Many derived features show correlation with such large scales and appear to suppress shine. They occur most frequently in forms from dry habitats or forms that climb in vegetation away from the ground, situations where dirt adhesion is less of a problem. Microornamentation differences involving other parts of the body and other squamate groups tend to corroborate this functional interpretation. Microornamentation features can develop on lineages in different orders and appear to act additively in reducing shine. In some cases different combinations may be optimal solutions in particular environments, but lineage effects, such as limited reversibility and different developmental proclivities, may also be important in their genesis. The fine pits often found on cell surfaces are unconnected with shine reduction, as they are smaller than the wavelengths of most visible light.

×

The microornamentation of the scales (oberhautchen) has been studied by means of enamel casts (in negative), or with detached skin pieces (positive cast in the upper face or negative in their lower face of the scales) and its observation by transparency with optical microscopy at 40x, 400x and 1000x. In this study we have found a remarkable uniformity in all genera of Lacertini studied (already known, although significantly expanding the number of species previously studied). In light of the results obtained, it seems that the use of the microornamentation of the scales in taxonomy is limited. There is a remarkable degree of variation and probably of homoplasy, as it happens in so many characters of Lacertini. Nor is it clearly linked to certain conditions of the environment, although it may have a certain importance in mechanisms such as evapotranspiration and perhaps in the crypsis through its influence on the reflectance of the scales. These scales can present protuberances (like small tubercles) on their surface (derived character) in Algyroides (the four species), and in the case of Algyroides marchi also seems to present small pits on its scale surface. In most lacertids the cells of the “oberhautchen” are usually narrow (or short anteroposteriorly, if preferred), between 1 and 4 μm, having the appearance of ribbons or transverse straps. Smaller sizes (derivated) appear more or less marked in Algyroides spp, Darevskia praticola complex, Parvilacerta spp and in Dinarolacerta mosorensis (although not in D. montenegrina) and is difficult to interpret. Except in Dinarolacerta, in the other species it coincides that they are ground or ground-rock interface species, and the coarser stripes could have to do with reflectance (imitating the vegetation or the medium between which they move, according to the hypothesis of Allam et al.). In the case of Dinarolacerta, very saxicolous, it is probably the sister group of Algyroides and the common morphology could have a phylogenetic origin linked to its relationship with Algyroides. There is also no relationship with moisture since some come from dry places and others are from very wet areas. The posterior flange of the cells may be slightly mounted in the next cell (primitive character) but appears quite raised (derived character) in Algyroides nigropunctatus (much less in A. moreoticus and A. marchi, and apparently little or nothing in A. fitzingeri). The rear flange of the cells can be smooth, corrugated or notched. In our samples, irregular (and even dentate) posterior ridges appear in numerous Darevskia such as D. derjugini, D. parvula, D. raddei complex [D. raddei raddei, D. r. vanensis and D. nairensis], in part of the group of D. rudis [D. rudis sspp. and D. bithynica sspp.], several Iberolacerta (I. bonnali, I. horvathi and I. monticola astur), as well as in Teira dugesii. The character appears, although less marked in Algyroides (more in A. moreoticus, but less marked or barely visible in the others), in Hellenolacerta graeca, and other Iberolacerta (I. aurelioi, I. martinezricai, and scarcely marked in I. cyreni). Very little marked in Darevskia mixta, somewhat more in D. dryada and none in D. clarkorum, and also appears in the group of D. saxicola (D. saxicola, D. brauneri brauneri, D. b. darevskii, D. lindholdmi, D. szczerbaki), Dalmatolacerta oxycephala, Dinarolacerta mosorensis (only in the Biokovo sample, and not in Durmitor or D. montenegrina), Apathya cappadocica, in some places of the scales of Parvilacerta fraasii (but not in P. parva) and very little in D. (p) hungarica; also in the remaining group of D. rudis (D. valentini valentini, D. v. lantzicyreni, D. rudis bolkardaghica, D. portschinskii), and some parthenogenetic species (D. armeniaca, D. dahli, D. rostombekowi) but not in D. unisexualis, D. uzzelli, D. sapphirina, D. bendimahiensis or in the triploid hybrid between D. unisexualis and D. nairensis. In these parthenogenetic species it seems a general rule that the character of the crenulation or irregularity of the posterior flange of the cells resembles that of the paternal rather than the maternal species. The exception is the triploid hybrid [arisen from the hybridization of D. unisexualis (parthenogenetic female, without the character) and a male of D. nairensis (with fairly developed character)] that lacks character, and in this case is more similar to the maternal species of which has two genetic sets compared to only one of the paternal one.

×

This study examines in detail the sequences of morphological differentiation and deduces mode of migration into specific layers of all types of neurons present in the optic tectum of the lizard Gallotia galloti. It complements previous similar work on tectal histogenesis in the chick. It was found that the neuronal population diversity in the lizard tectum can be reduced by developmental analysis to three neuroblast classes, called Types I, II and III. These classes correspond closely to those present in the developing avian tectum. Neurons belonging to each developmental class were characterized by their initial polarity, mode of translocation into the mantle layer and pattern of sprouting of primary axonal and dendritic processes. Each class produced along time a subset of the cell types distinguished in the mature tectum. Some aspects of sauropsidian tectal histogenesis are also common of other vertebrates, suggesting that fundamental mechanisms of tectal neuronal differentiation are conserved in tetrapods. Analysis of evolutive differences of tectal structure points to changes affecting the layering and perhaps the population size of specific cell types. Whereas tectal cell-type homology can be easily fundamented on embryological evidence and seems to be consistent with hodological and, to some extent, functional homology, the periventricular, central and superficial strata of the tectum are heterogeneous in cellular composition in different species and therefore represent analogous, rather than homologous entities.

×

Die Thermoregulation von Gallotia galloti von Teneriffa wurde im Frühjahr und im Herbst untersucht. Die vorläufigen Ergebnisse weisen darauf hin, daß die Art über ein hohes Maß an thermischer Unabhängigkeit verfügt in bezug auf Substrat- und Lufttemperatur.

×

Females of Gallotia galloti on the island of Tenerife usually produce 3 to 6 eggs, the exact number being correlated to the size of the female. The present data is based on the study of 39 egg bearing females captured over several years.

×

Die geographische Variation von 6 Schuppenmerkmalen der Gallotia galloti von 17 Fundstellen der Insel Teneriffa wurde mit Hilfe der Kanonischen Varianzanalyse untersucht. Es besteht ine signifikante Übereinstimmung in der geographischen Variation der Beschuppung von Männchen und Weibchen. Die Abgrenzung der multivariaten Felder zeigt, daß die geographische Variation der Beschuppung einem Nord-Süd-Klin folgt.

×

The longevity of several lacertid lizard species in captivity is reported. The conditions of keeping, which have been successful throughout many years, are briefly presented.

×

The lizard species Gallotia atlantica, G. caesaris, G. galloti eisentrauti, and G. stehlini from the Canary Islands and Teira dugesii from Madeira were kept and bred in captivity. Since ecological data concerning the breeding biology of these species are rare, the results of several years of captive breeding are presented. Data were collected from six pairs of G. atlantica during five years. The females laid 1-3 clutches of eggs each year between April and the beginning of September. The first egg clutches of a year contained 2.7 (1-5) eggs and the second egg clutches consisted of 2.5 (1-4) eggs. Third egg clutches were rare and consisted of only 1.7 (1-2) eggs. The baby lizards hatched after 73 (64-87) days. Three pairs of G. caesaris were observed during three years. Between the middle of May and the end of July the females of this species laid one clutch per year containing 3.8 (3-5) eggs. Only one female produced a second clutch during one season. The young hatched after 67 (64- 69) days. Eight pairs of G. g. eisentrauti were observed during seven years. Between the beginning of May and the end of August these females oviposited annually 1-2 clutches, which contained 4.7 (2-9) eggs in the first clutch of a year and 3.4 (2-6) eggs in the second annual clutch. The young hatched after 73 (62-89) days. One pair of G. stehlini was observed over a period of six years. Between June and August this female produced annually one clutch containing 9.8 (5-14) eggs. The young hatched after 80 (75-86) days. Two pairs of Teira dugesii were observed during one year and two pairs during four years. Between the end of April and the middle of August the females produced 1-2 clutches per year with 2.6 (2-3) eggs in the first and 2.1 (1-3) eggs in the second clutch of a year. The incubation period of the eggs was 72 (59-93) days. Furthermore, sizes of hatchlings of all species are presented. Colour patterns of hatchlings of G. g. eisentrauti, G. caesaris, and G. atlantica are described. Observations concerning the raising of the young in captivity are reported.

×

Intra- und interspecific variation are analysed fpr the post-natal skull of the lacertid lizards Gallotia galloti, Actnhodactylus erythrurus, Algyroides marchi, Lacerta monticola, Lacerta vivipara, Podarcis bocagei, Podarcis hispanica, Podarcis muralis, Psammodromus algirus and Psammodromus hispanicus. Individual variations identified include: the prsence/absence, number and morphology of some structures, mainly in the lacrimal, sclerotic ossicles and macilla; the number and location of foramina and the degree of ossification of some processes in chondrocranial bones. No differences bones. No differences have been found between the sexes with respect to presence and morphology of the bones but some species show sexual dimorphism in the size and robustness of the head and this may be reflected in the individual. The most substantial variations seen are ontogenetic: the appearances of new traits; development of articulations; differences between species in the timing of the stages of development of a given structure; changes in the relative position of some cranial elements; and the degree of calcification or ossification of processes. A total of 63 characters showing interspecific variations are identified. Some have not previously been described while others used in previous studies are redefined here on the basis of new morphological information obtained.

×

The comparative distribution of peptidergic neural systems in the brain of the euryhaline, viviparous teleost Poecilia latipinna (green molly) was examined by immunohistochemistry. Topographically distinct, but often overlapping, systems of neurons and fibres displaying immunoreactivity (ir) related to a range of neuropeptides were found in most brain areas. Neurosecretory and hypophysiotrophic hormones were localized to specific groups of neurons mostly within the preoptic and tuberal hypothalamus, giving fibre projections to the neurohypophysis, ventral telencephalon, thalamus, and brain stem. Separate vasotocin (AVT)-ir and isotocin (IST)-ir cells were located in the nucleus preopticus (nPO), but many AVT-ir nPO neurons also displayed growth hormone-releasing factor (GRF)-like-ir, and in some animals corticotrophin-releasing factor (CRF)-like-ir. The main group of CRF-ir neurons was located in the nucleus recessus anterioris, where coexistence with galanin (GAL) was observed in some cells. Enkephalin (ENK)-like-ir was occasionally present in a few IST-ir cells of the nPO and was also found in small neurons in the posterior tuberal hypothalamus and in a cluster of large cells in the dorsal midbrain tegmentum. Thyrotrophin-releasing hormone (TRH)-ir cells were found near the rostromedial tip of the nucleus recessus lateralis. Gonadotrophin-releasing hormone (GnRH)-ir cells were present in the nucleus olfactoretinalis, ventral telencephalon, preoptic area, and dorsal midbrain tegmentum. Molluscan cardioexcitatory peptide (FMRF-amide)-ir was colocalized with GnRH-ir in the ganglion cells and central projections of the nervus terminalis. Melanin-concentrating hormone (MCH)-ir neurons were restricted to the tuberal hypothalamus, mostly within the nucleus lateralis tuberis pars lateralis, and somatostatin (SRIF)-ir neurons were numerous throughout the periventricular areas of the diencephalon. A further group of SRIF-ir neurons extending from the ventral telencephalon into the dorsal telencephalon pars centralis also contained neuropeptide Y (NPY)-, peptide YY (PYY)-, and NPY flanking peptide (PSW)-like-ir. These immunoreactivities were, however, also observed in non-SRIF-ir cells and fibres, particularly in the mesencephalon. Calcitonin gene-related peptide (CGRP)-like-ir had a characteristic distribution in cells grouped in the isthmal region and fibre tracts running forward into the hypothalamus, most strikingly into the inferior lobes. Antisera to cholecystokinin (CCK) and neurokinin A (NK) or substance P (SP) stained very extensive, separate systems throughout the brain, with cells most consistently seen in the ventral telencephalon and periventricular hypothalamus. Broadly similar, but much more restricted, distributions of cells and fibres were seen with antisera to neurotensin (NT) and vasoactive intestinal peptide (VIP). Although in most cases the exact chemical natures of the immunoreactive substances are unknown, the results suggest that many peptides related to those proposed as neurotransmitters in the mammalian nervous system are present in specific neuronal systems in the teleost fish brain.

×

The polymorphism exhibited by the Canarian lizard Lacerta galloti on Tenerife is described. Four different phenotypes are distinguished the distribution of which can be correlated with the occurrence of old basaltic lavas. These basaltic areas are the most ancient parts of the island and presumably have been four independent islands before the birth of Teide volcano. Older and new evidence is presented and discussed with regard to the possible recent existence of a giant Lacerta (L. simonyi ! goliath group) on Tenerife. lt is demonstrated that all evidence concerning giant lizards fits with the distributional pattern stated for L. galloti. The possibility is discussed that the giant lizards of Tenerife have become extinct not before the turn of the century, or that they even might have survived until the present. One main objective of this paper is to stimulate future research.

×

Die Insel Teneriffa (Kanarischer Archipel) wird von zwei Unterarten von Gallotia galloti bewohnt, von denen die Nominatform im Zentrum und im Süden lebt. Für sie wird ein Lectotypus designiert, und die terra typica wird auf das Tal von Güimar restringiert. Die größere und buntgefärbte Form der Anaga-Halbinsel und der Nordküste wird als Gallotia galloti eisentrauti ssp.n. (terra typica Bajamar) beschrieben. Das Vorkommen zweiter distinkter Unterarten, die auch sekundäre Kontaktzonen ausbilden, wird historisch diskutiert und stützt die Hypothese, daß Teneriffa ursprünglich aus mindestens zwei getrennten Teilen bestanden hat. Die Verbreitung von G. galloti auf den vier westlichen Kanaren-Inseln Teneriffa, Gomera, Hierro und La Palma wird mit derjenigen anderer Echsenarten dieser Inseln vergleichend diskutiert.

×

Die Beziehungen der beiden rezenten kanarischen Rieseneidechsenarten Gallotia simonyi und G. stehlini werden diskutiert. Der Lebensraum und, soweit bekannt, die Lebensweise werden beschrieben. Es folgen einige Bemerkungen über die vom Aussterben bedrohte G. simonyi und abschließend einige Hinweise zur Haltung von G. stehlini im Terrarium.

×

Gallotia galloti gliedert sich in 6 Unterarten (G. g. galloti, G.g. caesaris, G. g. eisentrauti, G. g. gomerae, G. g. insulanagae und G. g. palmae) deren Beziehungen diskutiert und deren Lebensraum und Lebensweise beschrieben werden. Es folgen kurze Hinweise zur Terrarienhaltung. Abschließend wird auf neueste Forschungsergebnisse zur kanarischen Herpetofauna hingewiesen.

×

Dieser Beitrag ist der erste Teil einer Serie über die Herpetofauna der Kanarischen Inseln, in dem es zunächst auf die Lage, das Alter und die Entstehung des Archipels eingegangen wird. Bemerkungen zur Topographie, zum Klima und zur Vegetation geben Hinweise auf die Umweltbedingungen für die hier lebenden Amphibien und Reptilia. Herkunft und gegenwärtige Situation der endemischen Arten werden diskutiert, und es folgen Bemerkungen zu den nur fossil bekannten Arten Testudo burchardi, Gallotia goliath und G. maxima: Folgende Arten wurden auf den Inseln eingeschleppt: Hyla meridionalis, Rana perezi, Chamaeleo chamaeleon, Hemidactylus turcicus und Tarentola mauritanica. Den Abschluß dieses Beitrages bildet ein Schlüssel zum Bestimmen aller gegenwärtig von den Kanarischen Inseln bekannten Arten und Unterarten.

×

Das kleine »Galapagos vor der europäischen Haustür« ist Gegenstand dieses in sich geschlossenen Bandes. Er gibt erstmalig einen Überblick über die Herpetofauna dieser Inselgruppen.

×

In the herpetological collection of ZFMK 528 scientific species group names are represented by type materi- al. Of these, 304 names are documented by primary type specimens (onomatophores) while for 224 further names sec- ondary type specimens (typoids) are available, ranging chronologically from 1801 to 2010. The list is a shortened pred- ecessor of a comprehensive type catalogue in progress. It lists name bearing types with their catalogue numbers includ- ing information on further type series members also in other institutions, while secondary types are listed only by pres- ence, both in ZFMK and other collections including holotype repositories. Geographic origin and currently valid names are also provided.

×

1. The mating-bite of the Canarian Lacerta-species L. atlantica, L. galloti and L. simonyi carried out in the neck region represents no function of ehe different size between ehe sexes. lt is a character distinguishing these species from most other lacertids, especially from L. lepida. 2. The different types of mating-bite are intraspecifically constant and atelic characters, thus of taxonomic value. They are suitable for defining bundles of closely related species. 3. They cannot be recorded only by observing living animals, but also be concluded from bive scars in preserved females. 4. Preserved material shows that the species incertae sedis L. princeps and L. jayakari likely mate by means of neck-bite. 5. Phylogenetically ehe neck-bite is considered to be the primitive, the flank-bite ehe derived condicion. 6. The occurence of neck-bite in Mesalina shows, that the derived f!ank-bite must have evolved independently several times, thus representing no synapomorphy for the whole family. 7. The character mating-bite is not yet able to support generic diagnoses (Gallotia sensu ARNOLD 1973), as in other genera (Psammodromus) both types occur. Either one doubts, from this point of view, the monophyly of the latter, or one could also advocate a genus Timon containing besides L. lepida and the Canarian species also L. princeps and L. jayakari. Within this disjunct group with primitive mating-bite pattern, then, only L. lepida would have passed through a progressive development, also in respect of its maving behaviour. 8. To solve this dilemma, further investigations of lacertid mating behaviour, espe- cially courtship, will be necessary. They must be extended also to other lizard families. For this purpose the aid of terrarists is requested.

×

Vocalizations of the Iberian lacertids Psammodromus algirus and P. hispanicus as well as of the Canarian endemic Gallotia atlantica, G. galloti galloti, g. eisentrauti, G. caesaris, g. gomerae, g. palmae and G. stehlini were analyzed sonagraphically. The structure of the calls resembles those known from the families Pygopodidae (Lialis, Delma) and Iguanidae (Anolis) rather than those of Gekkonidae. The vocal repertoire of the lacertids is rather simple; it consists of clicks and various combinations of tonal and noisy components. Duration and frequency range of the sounds are variable; at least frequency range seems to vary with individual size, body temperature and the level of excitement. Most lizards vocalized when handled, but vocalization was also heard in free-ranging animals kept in cages and observed in the field. Sounds are uttered by inferior individuals defending a hide but also by dominant animals pursuing a rival. Field observations indicate that vocal activity is most intensive after sunset and may last until midnight. It is argued that vocalization in the highly territorial lizards of genus Gallotia may help regulate the high population densities, especially in the dark when optical signals do not work. The subtropical climate and the heat-gathering lava of the Canary islands make a nocturnal activity possible. The systematic significance of vocalization in Gallotia is discussed. Vocalization may be a synapomorphic character defining the genus Gallotia, but it is also present in Psammodromus and has been mentioned for Podarcis, Lacerta and Ichnotropis. From this, a multiple evolution can also not be excluded. Therefore, the common derived karyotype of the Gallotia species is the only established synapomorphic character justifying a separate generic but not at all familial rank for the Canary lizards.

×

In lizards, site selection is related to the acquisition of resources such as refuges, mates or prey, but also to the exploitation of sites suitable for thermoregulation. The latter process may be affected by lizard posture and body axis orientation in relation to the sun as a way to optimize heat exchange throughout the day. Specific postures and body orientations could also contribute to more efficient signal transmission in social contexts. In this paper we analyze activity and body axis orientation of adult males and females of the lacertid Gallotia galloti in two localities of Tenerife with different structural habitats. We performed transects at both sampling localities in the morning and at midday during May and June of three years (2002-2004). The numbers of lizards detected per unit time during transects at both localities were similar; however, significantly more males than females were detected. Moreover, more lizards were found oriented parallel or perpendicular to the sun than in alternative (oblique) orientations. Heating rates were not different for copper lizard models oriented parallel or perpendicular to the sun, neither in the morning nor at midday, and there was no significant relationship between air temperature and lizard body orientation. This suggests that lizard body orientation is not constrained by thermoregulatory requirements. We discuss alternative hypotheses and conclude that body axis orientation in G. galloti lizards may reflect a compromise between the conflicting demands imposed by thermoregulation and social communication.

×

In many species, male coloration signals aggressiveness and/or fighting ability. Males of the Tenerife lizard (Gallotia galloti) have conspicuous ultraviolet (UV)-blue cheek and lateral color patches that are brighter in the breeding season and larger than those of females. We analyzed experimentally the effect of morphological and behavioral traits, including spectral variables from UV-reflecting color patches, on the outcome of staged dyadic contests between males of two subspecies of G. galloti. We performed two experiments: (1) using pairs of unmanipulated males and (2) reducing the UV reflectance of the UV-blue patches of one of the contestants with sunscreen lotion. Results from experiment 1 showed no significant difference between subspecies in the effect of any variable on contest outcome. Overall, winners had larger body mass, head width, and fore-limb length and showed a higher rate of aggressive behavior patterns than losers, whereas losers showed a higher rate of “tail shake,” which is considered a submissive behavior. Winners also had lateral UV-blue patches with higher (more blue-biased) hue than losers, but no other spectral trait had a significant effect on contest outcome. Results from experiment 2 showed that reducing patch reflectance in the UV range had no effect in one subspecies but significantly increased fighting success in the other. The probability of winning was positively associated with the frequency of bites (irrespective of whether individuals had manipulated patches or not). Results from both experiments suggest that while multiple traits (morphometric, coloration, and behavioral) may influence the outcome of male contests in G. galloti, behavioral traits take prevalence over morphological, including coloration, traits.

×

We present preliminary results on the application of the observational ethological method to the study of activity of lizards from Tenerife in two habitats of the island with different ecological characteristics: Malpaís de Güimar (SE of the island) and the periphery of Teide National Park (centre of the island), and in two daily times. We counted the number of animals of each sex and category while walking in transects with hazardously chosen directions. The behaviour pattern performed by each observed animal was also scored. The results show that there were always more active males than females or juveniles in both zones. The number of total active animals per unit area and time was inversely related to the environmental temperature in Teide National Park. In Malpaís de Güimar the higher number of animals was recorded in intermediate temperatures between maximum and minimum ones. The number of observed animals was greater at midday than in the morning in Malpaís de Güimar, but the contrary occurred at Teide N.P. The results support the finding in other species of a higher activity level in males and also suggest a differential activity pattern in relation to environmental temperature in both zones studied.

×

Body coloration is sexually dimorphic in many vertebrate species, including lizards, in which males are often more conspicuous than females. A detailed analysis of the relative size of coloured patches and their reflectance, including the ultraviolet (UV) range, has rarely been performed. In the present work we quantified sexual dimorphism in body traits and surface area of all lateral patches from adult females and males of two subspecies of Gallotia galloti (G. g. galloti and G. g. eisentrauti). We also analysed the magnitude of sexual dichromatism in the UV-visible reflectance of such patches and the changes in patch size and brightness during the reproductive season (April–July). Males had significantly larger patch areas (relative to their snout-vent length) and higher brightness (mainly in the UV-blue range) than did females in both subspecies. The comparison of relative patch areas among months did not reach statistical significance. However, patch brightness significantly changed during the breeding season: that of the UV-blue (300–495 nm) range from lizards of the two subspecies was significantly larger in June than in April, while brightness in the 495–700 nm range in G. g. galloti was larger in May, June, and July than in April. A different pattern of dichromatism was also detected in the two populations, with G. g. eisentrauti being more sexually dichromatic than G. g. galloti. We discuss the results in terms of possible evolutionary causes for the sexual dichromatism related to different ecological characteristics of the habitats where each subspecies live.

×

Ambientali, Università degli Studi di Milano, Milano, Italy 3Laboratoire d’Ecologie Alpine, University Grenoble Alpes, University Savoie Mont Blanc, CNRS, LECA, Grenoble, France 4Kosmos – Museo di Storia Naturale dell’Università di Pavia, Pavia, Italy 5Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy 6I.P.L.A., Istituto per le Piante da Legno e l`Ambiente, Torino, Italy Correspondence Gentile Francesco Ficetola, Dipartimento di Scienze e Politiche Ambientali, Università degli Studi di Milano, Via Celoria 10, 20126 Milano, Italy. Email: francesco.ficetola@gmail.com Funding information Italian Ministry for Research, Grant/Award Number: 2017KLZ3MA Editor: Ana Margarida Coelho dos Santos Abstract Aim: Analyses of biogeographical patterns and macroecology of islands require large datasets reporting the occurrence of species. The Mediterranean region is a biodiver- sity hotspot, which hosts a large number of reptile species and has been the focus of many studies. Nevertheless, comprehensive inventories describing the features and biodiversity of these environments are lacking. We gathered a dataset summarizing data on reptile distribution on islands of the Mediterranean basin and Macaronesia, also including detailed information on the geographical features. Location: Islands from the Mediterranean Basin, the Atlantic Ocean within the Mediterranean biogeographical region, and Macaronesia (Canary and Savage Islands, Azores, Madeira and Cape Verde). Time period: Present. Taxon: Reptiles (squamates and turtles). Methods: Initially, we developed a geographical database describing islands of the study region, then gathered information on reptile occurrences from 757 bibliograph- ical sources, including atlases, published papers and the grey literature. Through a critical review of these sources, we also obtained information on the status of popula- tions (native, island endemic or non-native) and on the reliability of occurrence data. Results: We obtained basic geographical information from 1875 islands covering the whole study region and with a very broad range of geographical features. We gath- ered >4150 records of reptile occurrence on islands, referring to 198 taxonomic units (species or species complexes); information on population status was available for 84.9% of records. Data are provided as comma-delimited text files. Main conclusions: The database provides a key resource for biogeographical analyses and can also serve as a backbone for conservation studies. The availability of a large database on island features can also be useful for biogeographers working on other taxonomic groups. Nevertheless, more data are required for some geographical areas, in order to ascertain the status (e.g., native vs. non-native) of many populations and to understand the interplay between natural and human-driven processes.

×

n response to two previously published accounts, it is pointed out that successful incubation of lizard eggs does not primarily depend on the medium on or in which the eggs rest, nor on the incubator. Successful incubation is solely based on the two physi- cal variables of humidity (measured as water potential in kPa) and temperature. When these variables are within the proper range (-400/-150 kPa and 25-30°C) then the chief criteria are met. The inaccurate suggestion that the sex of lacertids is re- lated to incubation temperature is rejected because the gender of the young in this group of reptiles is determined genetically. The single report cited in the scientific literature that discussed TSD in a lacertid (Podarcis pityusensis) is refuted by consid- ering larger samples of incubated eggs. Similarly, reports that water potential of the substrate affects sex determination have also been discredited in the scientific lit- erature. The sometimes in hobby literature propa- gated short, artificially induced additional hibernation soon after the summer to bring on an additional reproductive period with egg production in November/December, is objectionable. The stress on the animals is such that the health of the lizards is com- promised. Moreover, among serious reptile enthusiasts there is only a limited demand for lacertids, discounting the need for so many offspring.

×

The interspecific relationships among female size, clutch size, egg size, and hatchling size were examined for 64 European lacertids. The eggs of all species increased linearly in both linear dimensions and mass during incubation. Across species initial egg mass was positively correlated with juvenile mass, with an allometric relationship exponent of 0.87. Initial egg mass across species increased proportionally with female mass to the power of 0.57. Moreover, an increase in maternal mass was also accompanied by an increase in clutch size. The number of eggs per clutch across species scaled with female mass to the power of 0.39. Removing the effect of female mass resulted in a negative correlation between egg mass and clutch size. Species for which the average egg size was lower than expected on the basis of female mass, tended to have larger relative clutch size. The total egg mass per clutch was about one third of female mass (exponent 0.94).

×

During the nineteenth century, single individuals of Gallotia galloti (OUDART 1839) have been reported from Madeira, believed to have been introduced by man. A small group has now (February 1992) been recorded in the botanical garden in the northeastern part of Funchal, assumed to be due to a recent introduction. It is speculated whether the species will be able to survive on Madeira. The climate of southern Madeira is quite similar to that of parts of the Canary Islands inhabited by G. galloti. But on the other hand, G. galloti has apparently not been able to survive on Madeira after previous introductions.

×

Geographical variation among contiguous populations is frequently attributed to ecological divergence or historical isolation followed by secondary contact. Distinguishing between these effects is key to studies of incipient speciation and could be revealed by different genomic signatures. We used RAD-seq analyses to examine morphologically divergent populations of the endemic lizard (Gallotia galloti) from the volcanic island of Tenerife. Previous analyses have suggested ecological and historical causes to explain the morphological diversity. Analyses of 276483 single nucleotide polymorphisms (SNPs) from >20 Mbp of the genome revealed one genetically divergent population from Anaga, a region associated with divergent mtDNA lineages in other Tenerife endemics. This population also has a high number of private alleles, and its divergence can be explained by historical isolation. Bayesian outlier analyses identified a small proportion of SNPs as candidates for selection (0.04%) which were strongly differentiated between xeric and mesic habitat types. Individual testing for specific xeric-mesic selection using an alternative approach also supported ecological divergence in a similarly small proportion of SNPs. The study indicates the roles of both historical isolation and ecological divergence in shaping genomic diversity in G. galloti. However, north-south morphological divergence appears solely associated with the latter and likely involves a relatively small proportion of the genome.

×

Cytological and molecular evidence is provided to characterize the sex chromosomes of several species of Lacertidae. Observations on pachytene and lampbrush stages show that sex chromosomes have different condensation cycles and are only partially paired during meiosis. Bkm probe hybridization to Pst I-treated genomic DNA of Podarcis sicula and Lacerta vivipara shows the same pattern both in males and females. In situ hybridization of the same probe to Lacerta vivipara chromosomes shows no preferential localization of this DNA sequence. The results obtained clearly exclude the possible involvement of Bkm in sex-chromosome differentiation in the species investigated.

×

Lacertids are the dominant group of lizards throughout the Mediterranean Basin. Their role in food web transfer of matter and energy from arthropods and other small invertebrates to birds and mammals constitutes a major function within Mediterranean ecosystems. For many years, prey consumption by lacertids was thought to be almost indiscriminate, not much more than a byproduct of habitat use. However, increasing evidence does not support this passive view. Analyses of prey availability have revealed active prey selection/avoidance in several species. Others show an internal tendency (i.e., historical constraints) to consume specific animal items (ants, clumped prey) or plant matter (seeds, nectar, pollen, leaves). Behavioural experiments showed that lacertids not only identify different prey types by both visual and chemical cues but also modify their feeding behaviour integrating past experiences. Furthermore, size, sex, reproductive state, body condition, tail loss and probably other lizard features are relevant for feeding ecology. However, less attention has been devoted to abiotic factors such as temperature and humidity. More experimental studies of the influences of competitors, predators and parasites on diet are needed. Even though it is controversial, optimal foraging theory provides a conceptual background for future studies. The evolutionary history of the various lacertid lineages, which constrains their morphology and physiology and eventually produces exaptative traits, is to be considered as well. Finally, methodology in field sampling, lab work and statistical analysis needs to be developed. Recommendations are given as to when and where to sample, which compartment should be analysed, which is the appropriate sample size, how to assess trophic availability, which statistical descriptors should be used and how they should be compared.

×

Parental provisioning and breeding success of Eurasian Kestrel (Falco tinnunculus) has been widely studied in some continental populations but not in their island-dwelling counterparts. We studied breeding success of kestrels nesting in natural rocky cavities in southern xerophytic scrub of the oceanic island of Tenerife during eight breeding seasons and its relationships with the endemic Gallot`s Lizard (Gallotia galloti). We examined lizard provisioning to assess some hypotheses regarding parental provisioning (e.g. central place foraging, parental investment and territory quality). Kestrels nesting in better quality territories (i.e. better habitats for lizards) advanced laying date and increased clutch and brood size at hatching. This did not result in higher number of fledglings. Lizard biomass provided to the chicks did not decrease with increasing nestling age and was correlated positively with the number of nestlings and chick age. These findings support the hypothesis of parental investment. On considering nestling-rearing period in three 10-day phases, we found significantly lower mean mass of lizards delivered in the first phase than in the other two phases together, with no differences between the last two phases. We suggest that kestrels respond to enhance breeding success and fitness keeping a stable number and quality of fledglings.

×

The successful regrowth of retinal ganglion cell (RGC) axons after optic nerve (ON) axotomy in Gallotia galloti indicates a permissive role of the glial environment. We have characterised the astroglial lineage of the lizard optic pathway throughout its ontogeny (embryonic stage 30 [E30] to adults) by using electron microscopy and immunohistochemistry to detect the proliferation marker PCNA (proliferating cell nuclear antigen), the transcription factor Pax2 and the gliofilament proteins vimentin (Vim) and GFAP (glial fibrillary acidic protein). PCNA+ cells were abundant until E39, with GFAP+/PCNA+ astrocytes being observed between E37 and hatching. Proliferation diminished markedly afterwards, being undetectable in the adult optic pathway. Müller glia of the central retina expressed Pax2 from E37 and their endfeet accumulated Vim from E33 and GFAP from E37 onwards. Astrocytes were absent in the avascular lizard retina, whereas abundant Pax2+ astrocytes were observed in the ON from E30. A major subpopulation of these astrocytes coexpressed Vim from E35 and also GFAP from E37 onwards; thus the majority of mature astrocytes coexpressed Pax2/Vim/GFAP. The astrocytes were ultrastructurally identified by their gliofilaments, microtubules, dense bodies, desmosomes and glycogen granules, which preferentially accumulated in cell processes. Astrocytes in the adult ON coexpressed both gliofilaments and presented desmosomes indicating a reinforcement of the ON structure; this is physiologically necessary for local adaptation to mechanical forces linked to eye movement. We suggest that astrocytes forming this structural scaffold facilitate the regrowth of RGCs after ON transection.

×

Femurs of 73 Gallotia galloti caught in different localities and belonging to two subspecies living in Tenerife (Canary Islands) were analysed by skeletochronology. The bones possessed annual rings like in many other lizards. For a high percentage of individuals, a remnant of the embryonic bone and a birth line of arrested growth remained present throughout life because cortical resorption never completely removed the first annual rings. Thus the age of an individual can be directly calculated from the number of lines of arrested growth. In the sample studies here, the oldest lizards were at least 8 or 9 years old. They reached sexual maturity during their second or third year of life.

×

The Canary Islands have become a model region for evolutionary studies. We obtained 1.8 Kbp of mtDNA sequence from all known island forms of the endemic lizard genus Gallotia and from its sister taxon Psammodromus in order to reanalyze phylogenetic relationships within the archipelago, estimate lineage divergence times, and reconstruct the colonization history of this group. Well-supported phylogenies were obtained using maximum parsimony and Bayesian inference. Previous studies have been unable to establish the branching pattern at the base of the tree. We found evidence that G. stehlini (Gran Canaria) originated from the most basal Gallotia node and G. atlantica from the subsequent node. Divergence times were estimated under a global clock using Bayesian Markov Chain Monte Carlo methods implemented by three different programs: BEAST, MCMCTREE, MULTIDIVTIME. Node constraints were derived from subaerial island appearance data and were incorporated into the analyses as soft or hard maximal bounds. Posterior node ages differed slightly between programs, possibly due to different priors on divergence times. The most eastern Canary Islands first emerged just over 20 mya and their colonization appears to have taken place relatively quickly, around 17–20 mya. The subsequent node is consistent with cladogenesis due to colonization of Gran Canaria from the eastern islands about 11–13 mya. The western islands appear to have been colonized by a dispersal event from Lanzarote/Fuerteventura in the east to either La Gomera or one of the ancient edifices that subsequently formed Tenerife in the west, about 9–10 mya. Within the western islands, the most recent node that is ancestral to both the G. intermedia/G. gomerana/G. simonyi and the G. galloti/G. caesaris clades is dated at about 5–6 mya. Subsequent dispersal events between ancient Tenerife islands and La Gomera are dated at around 3 mya in both clades, although the direction of dispersal cannot be determined. Finally, we show that G. galloti is likely to have colonized La Palma more than 0.5 Ma after emergence of the island 1.77 mya, while G. caesaris from the same clade may have colonized El Hierro very soon after it emerged 1.12 mya. There are tentative indications that the large-bodied endangered G. simonyi colonized El Hierro around the same time or even later than the smaller-bodied G. caesaris. This study demonstrates the effectiveness of Bayesian dating of a phylogeny in helping reconstruct the historical pattern of dispersal across an oceanic archipelago.

×

Transportation infrastructure is a main cause of environmental change in forest landscapes worldwide. In the Canary Islands, a dense road system fragment the native Canarian pine and laurel forests causing potential changes in population densities of endemic lacertid lizards (genus Gallotia). Our aim was to assess road edge effects on relative abundance patterns of the endemic Gallotia galloti in both forests. We also explored the species–habitat relationships in this road-fragmentation context. We found that lizard relative density in relation to road edges differed between forests. Lizards were more abundant along edges and leeward interior, but virtually absent from the interior of the windward laurel forest. In the pine forest, lizards were present at three distances from edge, with a net decrease in abundance from edge to interior. These patterns may be explained partly by differences in vegetation structure regarding road proximity in each forest that potentially affect the helio- and thigmothermic character of G. galloti, and thus its habitat use. A general suggestion of this study is that road margins create corridors that may be used by native lizards for dispersal through inhospitable forest matrix. The high road density in Tenerife may have negative implications for the conservation of the genetic variability of G. galloti. At the island scale, increased communication between lizard populations through road corridors might increase homogenization of the gene pool. Ecological processes in which this lizard plays important roles may also experience changes along road edges.

×

Lizards present neuronal production throughout the telencephalon in their adult state, both naturally and after experimentally induced brain lesions. As in birds, lizards present seasonal behavioural variations. In birds, such variations have been shown to alter neuronal production. In birds and mammals, lack of stimuli or exposure to stress interferes with adult neurogenetic capacity. The effect of this type of study has not been performed with lizards. In the present study we used bromodeoxyuridine to label dividing cells in the ventricular walls of Gallotia galloti lizards during all four seasons and we investigated the effect of captivity on such proliferation. We found that G. galloti presented a particular distribution that differed from that previously described in other reptiles with respect to regions of greater or lesser proliferative rate. In addition, proliferative rate varied seasonally, with greater production of cells in Spring and low production in Autumn and Winter. Proliferative rate was significantly lower throughout the telencephalon and during all seasons in those lizards kept in captivity as compared with wild animals, even though photoperiod and temperature were similar to natural conditions. Our results indicate that cell production in lizards is species-dependent, varies with seasons and is significantly reduced in captive animals.

×

In a previous study we found a seasonal distribution of cell proliferation (the first stage of adult neurogenesis) in the telencephalic ventricular walls of the adult Gallotia galloti lizard. The aimof the present work was to determine the influence of seasonality on the subsequent migration of the resulting immature neurons. We used wild animals injected with bromodeoxyuridine and kept in captivity within 30 days. To confirm the neuronal identity of these cells, we used double immunohistochemical 5-bromo-2′-deoxyuridine (BrdU) and doublecortin (DCX, an early neuronal marker) labeling, as well as autoradiography after the administration of methyl-[3H] thymidine ([3H]T).We foundthat: (1) therateofcell division and/ormigration fromthe ventricular walls varied with the season, especially in regions related with olfaction. (2) Immature neuronlike cells appeared to migrate in an apparently radial and tangential way towards different parts of the telencephalic parenchyma. (3) We didnot observeultrastructurallymature neuronsuntil at least 90 days later, a period considerably greater than that reported for other species of vertebrates in similar studies.

×

Afficients to the habenular complex were studied by means of in vitro horseradish peroxidase retrograde labeling and anterograde control experiments in the lizard Gallotia galloti. The medial habenular nucleus was found to receive abundant afferent fibers from the nucleus of the posterior pallia] commissure and the nucleus scptalis impar. More restricted input comes from the nucleus eminen- tiac thalami and the nucleus of the stria medullaris. The lateral habenular nucleus is innervated by various fiber groups originating from the bed nucleus of the anterior commissure, the diagonal band nucleus, the lateral preoptic area, the anteriorentopcduncular nucleus, the lateral hypothalamic and mammillary areas, the nucleus of the stria medullaris. the area tegmentalis vcntralis and a scattered neuronal subpopulation in the large-celled dorsolateral nucleus of the dorsal thalamus. Habenulopctal fibers generally follow the stria medullaris, but hypothalamic, entopcduncularand dorsal thalamic afferents course through the dorsal peduncle of the lateral forebrain bundle in a transthalamic route. Mesencephalic ventral tegmental afferents ascend through the tractus retroflexus.

×

In order to test the usefulness of the in vitro HRP-labeling technique in the brains of small lizards, the fasciculus retroflexus was labeled in isolated brains of young specimens of the lizard Gallotia galloti by means of I IRP applied with the tip of a micropipctte located approximately midway along the descending course of the tract. Cells in the medial and lateral habenular nuclei were labeled rctro- gradely. Anterograde transport showed the course of the fasciculus retroflexus, first dorsoventrally into the paramedian prcrubral tegmentum and then longitudinally into the isthmic nucleus interpeduncularis. Some fibers spread dorsally into the mesencephalic and isthmic tegmental fields. A substantial bundle continues caudally into nucleus raphe parvocellularis. Other fibers diverge rostral- wards from the point of inflexion of the fasciculus, coursing longitudinally in the medial forebrain bundle into the basal telencephalon. Some fibers course ros- trally from the nucleus habenularis lateralis in the stria mcdullaris and could be followed to the dorsal septum.

×

The projection pattern of the ventral thalamic reticular nucleus onto the dorsal thalamus was studied in the lizard Gallotia galloti using in vitro horseradish peroxidase and fluorescent carbocyanine labelling techniques. Localized label deposits at three dorsoventrally spaced sites in the dorsal thalamus elicited retrograde transport into separate, though partly overlapping, medial, dorsolateral and ventrolateral sectors within an extended cytoarchjtectonic complex which may be globally identifiable as the reticular nucleus. Neurons found in the dorsolateral and ventrolateral sectors mainly corresponded to the cell group named nucleus ventromedialis (or nucleus of the dorsal supraoptic decussation) in the literature, whereas neurons labelled in the medial sector corresponded to the so-called dorsal hypothalamic nucleus. Sparser cells appear labelled in the superficially placed nucleus suprapeduncularis. Thalamotelencephalic fibers arising from the injected dorsal thalamic nuclei also project to the corresponding retrogradely labeled sectors within the reticular nucleus. These findings reveal a rough topographic organization in the connections of the extended reticular nucleus complex with the whole dorsal thalamus. This supports the hypothesis of hodological homology between this ventral thalamic formation in Gallotia and the mammalian thalamic reticular nucleus.

×

Contemporary study of molecular patterning in the vertebrate midbrain is handicapped by the lack of a complete topological map of the diverse neuronal complexes differentiated in this domain. The relatively less deformed reptilian midbrain was chosen for resolving this fundamental issue in a way that can be extrapolated to other tetrapods. The organization of midbrain centers was mapped topologically in terms of longitudinal columns and cellular strata on transverse, Nissl-stained sections in the lizard Gallotia galloti. Four columns extend along the whole length of the midbrain. In dorsoventral order: 1) the dorsal band contains the optic tectum, surrounded by three ventricularly prominent subdivisions, named griseum tectale, intermediate area and torus semicircularis, in rostrocaudal order; 2) a subjacent region is named here the lateral band, which forms the ventral margin of the alar plate and also shows three rostrocaudal divisions; 3) the basal band forms the basal plate or tegmentum proper; it appears subdivided into medial and lateral parts: the m+edial part contains the oculomotor and accessory efferent neurons and the medial basal part of the reticular formation, which includes the red nucleus rostrally; the lateral part contains the lateral basal reticular formation, and includes the substantia nigra caudally; 4) the median band contains the ventral tegmental area, representing the mesencephalic floor plate. The alar regions (dorsal and lateral) show an overall cellular stratification into periventricular, central and superficial strata, with characteristic cytoarchitecture for each part. The lateral band contains two well developed superficial nuclei, one of which is commonly misidentified as an isthmic formation. The basal longitudinal subdivisions are simpler and basically consist of periventricular and central strata.

×

I studies the thermoregulatory behavior of a field population of the Canarian lizard Gallotia galloti, using null hypothesis based on (1) the measurement of operative temperatures available in full sun and in the shade (Te), and (2) the distribution of randomly positioned models with respect to sun and shade. The activity curve of the lizard population was unimodal, with a pronounced peak in the morning and lower (though roughly constant) levels at later times of day. Activity levels were positively correlated with the difference between Te in the sund and Te in the shade, but negatively correlated with Te in the shade. The distribution of lizards into sun-shade categories was highly selective relative to paper models, with an overall daily selectivity pattern that was symmetrical around midday (selection of sunlit perches early and late in the day, shade seeking at midday, and random distribution at intermediate hours). The low dispersion of hourly mean operative temperatures at lizard perching sites relative to random locations of models (average values calculated weighting mean Tes with frequencies of sun-shade use and sun-shade availability) suggested a high degree of thermoregulatory precision. Dark, adult males basked for longer periods than juveniles, whereas subadults/Females showed intermediate basking times, which suggests that body size and color differences may play a role in behavioral thermoregulation by these lizards.

×

Plasma concentrations of aldosterone, sodium and potassium were measured in the lizard Gallotia galloti. Aldosterone concentrations in control animals were 29.48 ± 8.65 ng/dl, which falls within the range reported for this hormone in mammals. Peripheral sodium and postassium concentrations were 132.81 ± 2.28 and 5.77 ± 0.32 meq/l, respectively. Plasma aldosterone and sodium were negatively correlated. A positive relationship could be established between potassium concentration and aldosterone levels. Acute or chronic administration of exogenous aldosterone increased the circulating levels of this hormone, being maximal in chronically treated animals. However, although plasma concentrations of aldosterone were augmented by acute administration, the sodium concentration in the plasma was only elevated by chronic treatment. No further changes to potassium concentration could be observed under primary hyperaldosteronism conditions. The extent to which aldosterone may be implicated in the regulation of sodium and potassium transport in reptiles and its possible action on postrenal structures of electrolyte transport are discussed.

×

1. The effects of D-aldosterone on the electrical properties and ionic transport have been analysed (in vitro) in the colonic epithelium of the lizard, Gallotia galloti. 2. The injection of 30 g of D-aldosterone induced a significant rise of plasma aldosterone concentration, sustained for 4 hr after administration. 3. Intraperitoneal injections of D-aldosterone caused a slight reduction of transmural potential difference (PD) and short-circuit current (Isc). 4. Net absorption of Na+ across the colon from aldosterone-treated lizards did not increase when compared to colon from normal lizards. Cl- absorption was increased in treated lizards. 5. Addition of mucosal barium to treated tissues brought about a sustained increase of PD and Isc. 6. The absorption of fluid in normal lizards was reversed to fluid secretion in treated lizards. 7. The effects of D-aldosterone on lizard colon are compared with those reported for the colon of mammals and birds.

×

Contrary to what is usually believed, the specific name Lacerta galloti must be credited to Oudart (1839) instead of Duméril & Bibron (1839). The two specimens MNHN 2744 and 2744 A, collected in Tenerife by Webb & Berthelot, and figured by Oudart (1839), are the only syntypes of this species. Therefore, the designation by Boulenger (1920) of a third specimen (MNHN 2743) as lectotype of the species is not valid, and the designation by Bischoff (1982) of the specimen MNHN 2744 as lectotype, although posterior to that of Boulenger (1920), is valid.

×

Circadian rhythms are the oscillations of biological variables at regular intervals of time. Natural selection has favored the evolution of circadian rhythms and animals that adjust to the activity according to the most favorable environmental circumstances. However, the circadian rhythms persist demonstrating their endogenous character, but enter the rhythm of the free course “free running rhythm”. The parietal eye is part of the epithalamus, it is a photoreceptor organ and is associated with the pineal gland, regulating the circadian rhythm and hormonal production for thermoregulation. In reference to the circadian system, the pineal organ plays an important role in the regulation of rhythms. It has been shown that, through pinealectomy, marked changes have occurred in the periods of free course and arrhythmias in lizards. The hypothesis of this study is based on the effect of covering the parietal eye, blocking the arrival of the environmental light estimation to the pineal gland, which would cause a pronounced imbalance in the activity-inactivity rhythm. In the event that this pronounced desynchronization does not occur, it will be necessary to consider that there are other or other ways that synchronize the activity-inactivity rhythm in this species. The function of the pineal organ in the regulation of the circadian rhythm of the lancet Gallotia galloti. The experiment consisted in recording the circadian rhythm of the lizards in 3 different cycles. A first cycle consisted of 12 hours of light and dark, in the second cycle they were maintained in 24 hours of constant light and in the third cycle they returned to the conditions of the first cycle. The second part of the experiment consisted of performing the same procedure, but this time the parietal organ of the animal. For the analysis of the data, statistical analyzes, actograms and the cosinor method are used. The results indicate that the parietal eye in the Gallotia galloti species is not the main mechanism by which the pineal gland receives light information from the environment. If not, it could be assumed that there are signaling pathways in these animals.

×

Two new species of the genus Ophionyssus Mgnin, 1884 (Acari: Macronyssidae) are described, O. galloticolus spec. nov. parasitizing the lacertid lizard Gallotia galloti eisentrauti from Tenerife, Canary Islands, Spain, and O. setosus spec. nov. parasitic on Gallotia stehlini from Gran Canaria, Canary Islands, Spain.

×

Gallotia galloti insulanagae is a subspecies inhabiting exclusively the islet of “Roque de Fuera de Anaga” (Tenerife, Canary Islands). Here we provide data on biometry, population dynamics and abundance. We also include a description of the environment where it lives and trophic resources available. This subespecies was described in 1985. It differs from that of northern Tenerife because of its melanism and larger size. Ist habitat presents a low floral diversity and an abundant presence of marine birds. We have conducted census to estimate the population size in several campaigns. The population size is estimated in 350 specimens on the whole “Roque”, with an approximate density of 200 individuals per hectare. This density is higher than that observed for other lizards inhabiting similar environments. In spite of its isolation and apparent resource scarcity, the general status of the population is adequate. Furthermore, the sex ratio is close to one.

×

Bright colors and conspicuous visual displays have been described in many lacertid species. However, previous studies of lacertid coloration and behavior have largely ignored differences between the lizards´ and our own visual perception, including the possibility that the visual range of lacertids extends into the near ultraviolet (UV) region of the spectrum. In this study we use UV photography and reflectance spectrophotometry to document the presence and distribution of UV reflectance in color patches of Gallotia lizards from the Canary Islands. We found considerable reflection of UV light in blue, yellow, and green color patches of different Gallotia species. Fore example, the lateral and ventro-lateral blue patches of G. galloti from Tenerife show a single peak of reflectance with a maximum in the near UV waveband, close to the peak sensitivity of UV retinal cones in lizards with known UV vision. The blue, UV-reflecting patches are present in lizards of either sex. However, These are differences in the spectral shape of blue patches from male and female lizards, particularly in the UV range. We conclude that G. galloti are sexually dichromatic in their own visual world. Furthermore, we found large interindividual differences in the reflectance of blue patches in lizards from the same sex and population. These differences are again most marked in the UV region of the spectrum. We discuss possible functions of UV-reflecting patches in sex recognition, male-male contests, and mutual mate choice.

×

Circadian rhythms can be defined as specific adaptations of the various cycles presented by organisms to daily environmental oscillations. Evidence has been presented that most of the studied rhythms are endogenous, meaning that they are maintained despite the absence of environmental signals. In spite of their endogenous nature, these rhythms can suffer alterations by means of the modification of the environmental conditions. Over time a number of techniques have been developed for the study of different biological rhythms and in particular circadian rhythms. Although the sleep-wake rhythm is recognized as the most studied within circadian rhythms, it is comparable to the activity-inactivity rhythm, which will be understood as the basis of this work. This project will study the behaviour of a population of 14 organisms of the Gallotia galloti species in different light-dark cycles of 9 days duration (light-dark, constant light and constant dark) by recording their movements by a series of photoreceptor infrared sensors located on each side of an individual cage for each lizard. With the objective of observing the changes produced in the circadian rhythm of the individuals under study during the different cycles with different lighting conditions and to have more information on the functioning of the circadian system in reptiles. The results obtained show obvious variations in rhythm as different lighting periods are applied. It can therefore be said that the application of the different light-dark cycles involves significant changes in the regulation of the endogenous circadian rhythm of the lizard Gallotia galloti.

×

Motor activity of lacertid lizards (Gallotia galloti) was continuously recorded through sensitive platforms during some days in LD and later for up to 20 days in LL. Light intensity was 4.6 μE.s‐1.m2, both during light period of LD and in LL and temperature was maintained constant (28°C ±0.5). The circadian periods, calculated through periodogram analysis, were less than 24 h except in two lizards (out of 8) having a period somewhat longer than 24 h. Ultradian frequencies, obtained by means of a Fast Fourier Transform, were calculated for two consecutive segments of 64 data points (`morning”; and “afternoon”;, respectively) of each lizard and day. The ultradian peaks mainly fell into two bands: 9–36 c/day (= 160–40 min. period range) and 45–90 c/day (32–16 min). In most of the animals, the mean power of the first band was significantly greater (p < 0.05) than that of the second one, both in “morning”; and “afternoon”; segments, but for two lizards the mean power of the second band was significantly greater also in both data segments. These results are compared with those obtained in previous analyses of ultradian bands in LD.

×

Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome- wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some popu- lations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may con- stitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.

×

Communicative traits are strikingly diverse and may vary among populations of the same species. Within a population, these traits may also display seasonal variation. Chemical signals play a key role in the communication of many taxa. However, we still know far too little about chemical communication in some vertebrate groups. In lizards, only a fewstudies have examined interpopulational variation in the composition of chemical cues and signals and only one study has explored the seasonal effects. Here we sampled three subspecies of the Tenerife lizards (Gallotia galloti) and analyze the lipophilic fraction of their femoral gland secretions to characterize the potential interpopulational variation in the chemical signals. In addition, we assessed whether composition of these secretions differed between the reproductive and the nonreproductive season. We analyzed variations in both the overall chemical profile and the abundance of the two main compounds (cholesterol and vitamin E). Our results show interpopulational and seasonal differences in G. gallotia chemical profiles. These findings are in accordance with the high interpopulational variability of compounds observed in lizard chemical signals and show that their composition is not only shaped by selective factors linked to reproductive season.

×

Cells considered to be migratory in the cerebral cortex of adult lizards are ultrastructurally of two types. Nuclei in the first type have highly dispersed chromatin, creating a spongy appearance, whereas in the second type the chromatin is irregularly clumped. Both types of cells are closely associated with processes of radial ependymal glia cells, which perhaps orient their migratory pathways. Cells with spongy chromatin show an increase in cytoplasmic organelles and progressive chromatin condensation as they travel from the ependymal layer to the granular layer. Possibly these cells account for the neuronal increase that takes place in the granular layer during postnatal life. Cells with chromatin clumps are very scarce; ultrastructurally they resemble immature reptilian astroglia cells.

×

1. In the search for properties of the Kindling effect in the lizard Gallotia galloti and after testing about 400 animals, one of them produced a very high density of recurrent electrographic seizures without previous application of any epileptogenic treatment.2. Ten percent of the recorded time (four days, continuous recording) was spent in seizures of variable morphology.3. Oral administration of 3 mg/kg of diphenylhydantoin every 24 h completely abolished the seizures.

×

1.Lizards Gallotiu galloti received daily 3 mg/kg body wt of diphenylhidantoin (DPH) over a period of 15 days and at the same time the animals were kindled. 2. The progression of the kindling effect was evaluated by counting the number of spontaneous epileptiforrn potentials, the duration of afterdischarges and the duration of electroencephalographic spontaneous seizures. 3. The diphenylhidantoin treated group, relative to controls presented: (a) significant reduction in the duration of afterdischarges and spontaneous electroencephalographic seizures; and (b) increased frequency of the spontaneous epileptiform potentials.

×

1. The Canary Island lizard Gallotia galloti, tested in still air between 5 and 35°C, heated faster than it cooled. The ratio between heating and cooling thermal time constants shows no dependence on body weight and its value was 0.50 on average. 2. Regression equations for the relationship between the thermal time constant (τ) and body weight (W) during heating (h) and cooling (c) are: 3. During heating the core and subcutaneous body regions heat at the same rate, while during cooling the core cools more slowly than the subcutaneous area. 4. Heart activity differences during heating and cooling were restricted at body temperature range 7–20°C. The increased heart activity during heating appears to be a physiologically controlled response, as opposed to the decreased heart activity during cooling, which appears to be a passive response.

×

Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred base on nucleotide sequence of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eatsern-western geographic transect. The nearly extinct species Galloti simonyi from the most western island of El Hierro is closely related to the common western species Gallotia galloti. The nearest branch to this pair is Gallotia stehlini from the central island of Gran Canaria, and finally, Gallotia atlantica from the two eastern and geologically oldest islands appears as the most distantly related species of the group. At the statistical level, four subspecies can be recognized in G. galloti, but only two in G. atlantica.

×

1. The Canary Island lizard Gallotia galloti, tested in still air between 5 and 35”C, heated faster than it cooled. The ratio between heating and cooling thermal time constants shows no dependence on body weight and its value was 0.50 on average. 2. Regression equations for the relationship between the thermal time constant (t) and body weight (W) during heating (h) and cooling (c) are: Tb= 1.74 W056 Tc = 2.42 W066. 3. During heating the core and subcutaneous body regions heat at the same rate, while during cooling the core cools more sfowly than the subcutaneous area. 4. Heart activity differences during heating and cooling were restricted at body temperature range 7-20°C. The increased heart activity during heating appears to be a physioIogicaIly controlled response, as opposed to the decreased heart activity during cooling, which appears to be a passive response.

×

Oceanic islands are places where biological assemblages are relatively simple, as compared to the mainland. On islands, however, pollinator assemblages may to be composed of a taxonomically disparate group of organisms (e.g. insects, lizards, and birds), some of them with opportunistic nectar-feeding behaviour. Here we investigated some components of pollination effectiveness of Lotus maculatus (Fabaceae), an endangered Canary Islands endemic. In a flower exclusion experiment, we bagged flowers and compared their subsequent fruit and seed set to that of control flowers. Number of interactions with vertebrate and invertebrate flower visitors was counted and it was recorded whether interactions were legitimate (potentially pollinating) or non-legitimate (nectar robbing). Additionally, we estimated pollen loads on lizards and looked for any relationship between reproductive success of individual plants and number of visits made by the top three flower-visiting species (in terms of both frequency of occurrence at censuses and number of floral visits). Bagged flowers fruited less and with fewer seeds than control flowers. The only observed flower-visiting vertebrate was the Tenerife lizard Gallotia galloti, whose interactions were always legitimate and with around a half of captured individuals carrying pollen grains. The most frequent flower-visiting insect was the honeybee Apis mellifera followed by the solitary bee Lasioglossum arctifrons. The honeybee, however, was only a nectar robber, and the solitary bee was not an effective pollinator, but rather a pollen gatherer. Fruit set by individual plants was positively related only to frequency of visits by the lizard. Thus, the lizard seems to play a key role in the conservation management of L. maculatus.

×

1.1. The heart rate and motor activity of lizards (Gallotia galloti) maintained in a light-dark cycle (12:12 hr) and with changing cyclic temperature were recorded. Both variables showed a circadian pattern, motor activity variations leading heart rate by approximately 110 min.2.2. Results from cross spectral analysis showed that heart rate was highly correlated with temperature and both variables were changing practically in phase. However, motor activity and temperature were less correlated and in this case motor activity led temperature by approximately 100 min.3.3. In the ultradian range, two periodicities could be distinguished in the power spectra of motor activity and heart rate variations during the day: one between 0.019 and 3.9 × 10−3 cycles/min (central peak around 85 min period) and another, of lower power, between 0.05 and 0.02 cycles/min (central peak around 34 min period). During the night, only the heart rate showed both periodicities but with a lower amplitude.4.4. The presence of ultradian oscillations in heart rate during the night suggested that they do not depend on motor activity which was almost absent during that daily period.5.5. Motor activity and heart rate were also highly correlated in the ultradian range, motor activity leading heart rate by around 5 min at the 85 min main peak.

×

Electroencephalogram (EEG) from dorsal cortex of lizard Gallotia galloti was analyzed at different temperatures to test the presence of fractal or nonlinear structure during open (OE) and closed eyes (CE), with the aim of comparing these results with those reported for human slow-wave sleep (SWS). Two nonlinear parameters characterizing EEG complexity [correlation dimension (D2)] and predictability [largest Lyapunov exponent (l1)] were calculated, and EEG spectrum and fractal exponent b were determined via coarse graining spectral analysis. At 25°C, evidence of nonlinear structure was obtained by the surrogate data test, with EEG phase space structure suggesting the presence of deterministic chaos (D2 ,6, l1 ,1.5). Both nonlinear parameters were greater in OE than in CE and for the right hemisphere in both situations. At 35°C the evidence of nonlinearity was not conclusive and differences between states disappeared, whereas interhemispheric differences remained for l1. Harmonic power always increased with temperature within the band 8–30 Hz, but only with OE within the band 0.3–7.5 Hz. Qualitative similarities found between lizard and human SWS EEG support the hypothesis that reptilian waking could evolve into mammalian SWS.

×

Syntopic colonies of Gallot`s lizard and the Canary wall gecko were observed basking on a lava rock demarca- tion wall at a tourist resort on Teneriffe Island. While the lizards showed a reduced escape distance of about 40 cm towards humans, dogs, and pigeons, the geckos had assumed a nearly black colouration, matching that of the lava rock, and could be approached and picked up without their responding defensively. When a cat came strolling down the crown of the wall, the lizards suddenly reverted to escape distances of 5+ metres. Adults re- sponded first, triggering the flight of younger specimens. The geckos did not take notice of the passing cat, even though it walked by some as close as 25 cm. It would thus appear a.) that local lizards have learnt to differentiate between `harmless` (tourists, dogs, pigeons) and `potentially dangerous` (cats) passers-by; and b.) that younger generations learn appropriate defensive responses from older specimens. The lack of any defensive response by the geckos might have to do with a.) their being blinded by the bright sun, or b.) total reliance on camouflage. Comparative observations on Tarentola mauritanica on Gozo Island (Malta) seem to disprove the former expla- nation, as these would maintain escape distances of 5-10 m even in bright sunlight. These observation comple- ment, and in part contradict, previous summaries of these species` defensive behavioural patterns.

×

Es wird über die Sichtung einer in einem schlechten körperlichern Zustand befindlichen, aber dennoch agilen Gallotia galloti eisentrauti im Norden Teneriffas berichtet. Über die Bedeutung dieser Beobachtung für die Terrarist wird diskutiert.

×

In recent years there has been an exponential increase in the amount of published DNA sequences, as it has become one of the most popular sources of data for reconstructing phylogenies. A number of studies have attempted to resolve the relationships of groups of lacertids using mitochondrial DNA sequence data, in particular Podarcis and Gallotia (e.g. THORPE et al., 1994; 1996; GONZALEZ et al., 1996; FU et al., 1997; HARRIS, 1997; HARRIS et al., 1998a; 1999; CASTILLA et al., 1999a,b). Reassessment of these data suggest some alternative phylogenies to those previously published, and also highlight possible problems. Two studies have attempted to unravel the phylogeny of the whole family using mitochondrial DNA sequences (FU, 1998; HARRIS et al., 1998b). By combining these essentially congruent data sets, and reanalysing levels of support for the phylogenies produced, a more complete estimate of relationships across the family is produced. This is then compared to alternative sources of evidence, primarily morphological (ARNOLD, 1989), biochemical (MAYER & BENYR, 1994) and karyological (OLMO et al., 1993). Reasons for discrepencies are discussed, as are the relative advantages and disadvantages of the different sources of phylogenetic inference.

×

DNA sequences from parts of the 12S, 16S and cytochrome b mitochondrial genes, which totalled 1049 aligned base pairs, were used to estimate the relationships of 49 species of Lacertidae, including representatives of 19 out of the 23 recognized genera and 23 species of the paraphyletic genus Lacerta. These data were used, together with morphological information, to estimate the relationships within the family. Molecular evidence corroborates the monophyletic status of many genera and species groups originally based on morphology. It indicates that Psammodromus forms a clade with Gallotia, which is the sister taxon of all other lacertids. These comprise three units: the primarily Afrotropical armatured group; the largely Oriental Takydromus; and the west Palaearctic Lacerta and its derivatives, Podarcis and Algyroides. Morphology also supports the first three assemblages, but suggests that they are derived from a paraphyletic Lacerta. Within Lacerta and its allies, DNA sequence analysis corroborates the affinity of some members of each of the subgenera Lacerta s. str. and Timon, and of the L. saxicola group. It also supports the relationship of L. monticola, L. bonnali and L. horvathi, and suggests that the L. parva–L. fraasi clade and L. brandti are not related to Psammodromus–Gallotia, as morphology indicates, but instead are associated respectively with the L. danfordi and L. saxicola groups. DNA sequence data provide additional evidence that the eastern Arabian `Lacerta` jayakari and `L.` cyanura are members of the armatured clade and also sister species. Our analysis supports an origin for present lacertids in west Eurasia. The armatured clade invaded Africa, probably in the mid-Miocene, spreading widely and evolving increasingly xeric-adapted forms, one lineage of which later moved back into the Palaearctic. `Lacerta` jayakari and `L.` cyanura are assigned to Omanosaura, Lutz and Mayer 1986. The name Gallotiinae Cano, Baez, Lopez-Jurado and Ortega, 1984 is available for the Gallotia–Psammodromus clade, Eremiainae Shcherbak 1975 for the armatured clade and Lacertinae for Lacerta, Podarcis and Algyroides. Two new subgenera of Lacerta are proposed here: Caucasilacerta for L. saxicola and its allies, and Parvilacerta for L. parva and L. fraasi.

×

In June of 1996 the senior author discovered a new form of lizard in the Teno Massif, the westernmost part of Tenerife Island, which is very similar to the Giant lizard of El Hierro (Gallotia simonyi). The new lizard differs from the latter by its smaller size, morphological characters, and its very different pattern of coloration. To the present, only G. galloti, a smaller sized lizard, which is widely distributed on Tenerife, was known from this island. In this article, the recently discovered lizards and their habitat are briefly presented. Furthermore, the present knowledge of the status of the population and problems concerning the endangerment of these extremely rare reptiles are discussed.

×

The evolutionary diversification of many terrestrial vertebrate groups is strongly linked to climatic events in the Cenozoic, the period from 65 Million years ago to today when modern animals first appeared. I investigated the effects of Cenozoic climate change on the taxonomic and morphological diversification of the Old World lizard family Lacertidae, with particular emphasis on the African radiation. African lacertids exhibit an unusual pattern of diversification, in which their highest species richness occurs in deserts north and south of the equator, despite being spread throughout the continent. This disparity is particularly surprising given that desert lacertids are thought to be evolutionarily younger than their mesic-dwelling relatives, suggesting increased diversification rates in arid habitats. To identify the evolutionary factors underlying this pattern, I use a combination of phylogenetic, morphological and ecological techniques. In Chapter 1, I apply Bayesian methods and fossil-based calibrations to molecular sequence data to construct a time-calibrated phylogeny for Lacertidae. I estimate that the family arose in the early Cenozoic, with the majority of their African radiation occurring in the Eocene and Oligocene. In Chapter 2, I describe changes in lacertid body shape across biomes and substrates, and find widespread morphological convergence in similar habitat types. I suggest that in addition to foraging demands, fluctuating and extreme climatic conditions, largely driven by precipitation and temperature, contribute to morphological convergence across independent arid-dwelling clades. Finally, I test if ancestral transitions in ecology, morphology, and rates of diversification temporally coincide with paleoclimatic events in the Cenozoic. I use High Resolution X-ray Computed Tomography to characterize changes in the skull related to life in arid habitats, and apply maximum likelihood methods to test if the origins of those traits temporally coincide with significant shifts in habitat, diversification rates and climatic changes. My results show that African lacertids experienced three major peaks in diversification, accompanied by the evolution of suites of arid-adapted morphological traits. These changes coincide with climatic shifts in Africa, including the transition from closed forests to open grasslands and savanna in the late Oligocene, prior to the peak temperatures of the mid-Miocene Climatic Optimum, and following the formation of the Benguela current leading to hyper-aridity in southern Africa. I conclude that deserts are important centers for reptile evolution, but that expected changes in climate due to global warming may outpace the ability of arid-dwelling species to adapt and persist in the future.

×

Background: Although current molecular clock methods offer greater flexibility in modelling evolutionary events, calibration of the clock with dates from the fossil record is still problematic for many groups. Here we implement several new approaches in molecular dating to estimate the evolutionary ages of Lacertidae, an Old World family of lizards with a poor fossil record and uncertain phylogeny. Four different models of rate variation are tested in a new program for Bayesian phylogenetic analysis called TreeTime, based on a combination of mitochondrial and nuclear gene sequences. We incorporate paleontological uncertainty into divergence estimates by expressing multiple calibration dates as a range of probabilistic distributions. We also test the reliability of our proposed calibrations by exploring effects of individual priors on posterior estimates. Results: According to the most reliable model, as indicated by Bayes factor comparison, modern lacertids arose shortly after the K/T transition and entered Africa about 45 million years ago, with the majority of their African radiation occurring in the Eocene and Oligocene. Our findings indicate much earlier origins for these clades than previously reported, and we discuss our results in light of paleogeographic trends during the Cenozoic. Conclusion: This study represents the first attempt to estimate evolutionary ages of a specific group of reptiles exhibiting uncertain phylogenetic relationships, molecular rate variation and a poor fossil record. Our results emphasize the sensitivity of molecular divergence dates to fossil calibrations, and support the use of combined molecular data sets and multiple, well-spaced dates from the fossil record as minimum node constraints. The bioinformatics program used here, TreeTime, is publicly available, and we recommend its use for molecular dating of taxa faced with similar challenges.

×

Because sexual selection pressures are high in sexually dimorphic organisms, morphological, physiological and performance traits are often studied in a sexual selection context. The proximate mechanisms underlying evolutionary change in these traits, however, remain largely unstudied. Here, we examined the role of steroids in shaping morphology and physiological performance in males of a sexually dimorphic lizard (Gallotia galloti). We compared morphology and physiological performance of males with experimentally elevated testosterone levels to sham-operated males. Before surgery, inter-individual variation in plasma testosterone levels correlated positively with bite force capacity. Administration of exogenous testosterone resulted in an increase of the mass of both jaw closing and locomotory muscles compared with sham-operated individuals, but the responsiveness varied considerably among muscle groups. In contrast to our expectations, the dramatic testosterone-induced changes in muscle masses did not result in concordant changes in bite force performance or sprint speed.

×

1. Morphological characteristics (snout–vent length, badge area, mass, limb and head measures) and whole-animal performance capacities (sprint speed, acceleration capacity, stamina and bite force) were measured in male lizards, Gallotia galloti. These males were also tested in paired staged contests to assess relative fighting capacity and to link these results to morphology and performance. 2. A multivariate analysis of the four performance features revealed a clear difference between the physiological capacities of winners vs losers, with bite force being the most important predictor of the outcome of fights. 3. The finding that bite performance is linked to dominance fits in with the high sexual dimorphism in head size in this species, as head size is a predictor of bite force performance. 4. Winners of contests also tended to have larger total areas of blue patches on their sides, suggesting that these badges convey information on the social status of the males. However, since no correlation was found between bite force and badge size, the patches seem to contain information on a component of fighting capacity other than bite force.

×

Background and Aims Oceanic island ecosystems favor the appearance of novel interactions as a consequence of their depauperate and disharmonic flora and fauna. Echium simplex, endemic to the Anaga Biosphere Reserve in NE Tenerife, Canary Islands, belongs to the Canarian bird–flower element. Methods Along two flowering seasons, we studied its breeding system, identified the floral visitors, and compared the pollination effectiveness of different animal guilds (insects vs. vertebrates) by means of selective exclosures. Key Results The plant showed to be self‐compatible but selfing significantly reduced fruit set. The flowers were visited by five bird species (mostly Phylloscopus canariensis and Serinus canarius, but also Cyanistes teneriffae, Sylvia atricapilla and Sylvia melanocephala), a lizard species (Gallotia galloti), and over a hundred insect species (mainly hymenopterans and coleopterans). Flying insects increased fruit set whereas small flower dwellers (mostly beetles) decreased both fruit and seed set; by contrast, vertebrates had a negligible effect on reproductive success. Conclusions We conclude that despite the floral resources provided by E. simplex may be important to some vertebrate species, these do not appear to notably contribute to increase the fitness of the plant, which show to be more dependent upon flying insects to set fruits and seeds. We additionally found that plant reproductive structures are heavily damaged by feral goats, which threaten the maintenance of this Canarian endemic species.

×

The implementation of molecular tools in parasitology has led to the discovery of numerous cryptic species. However, detailed morphological studies are needed to evaluate the cryptic nature of such species, as well as to provide an appropriate and formal description. Recent phylogenetic analyses using mitochondrial and nuclear genes have revealed that the nematode Spauligodon atlanticus, parasite of lizards of the genus Gallotia endemic to the Canary Islands, consists of two highly divergent and unrelated lineages, one in the eastern islands and the other in the western ones. This study provides a detailed morphological analysis of the two S. atlanticus lineages characterized genetically, based on body measurements and scanning electron microscopy. This integrative approach revealed phenotypic differences between them, despite their overall morphological resemblance. As a result, the new species Spauligodon occidentalis sp. nov., from the formerly western lineage, is described. The morphological similarity between the two Spauligodon species is better explained on the basis of evolutionary convergence, since both species parasitize Gallotia lizards. In addition to delimiting the new nematode species, this study highlights the importance of combining genetic and morphological data with taxonomy to uncover the nature of cryptic species and decrease taxonomic uncertainty.

×

The distribution and the ratios between noradrenaline (NA) and adrenaline (A) cells in eight species belonging to the family Lacertidae were studied. There are variations in the distribution of the two cell types within the gland and a wide range of variation in the NA/A cell ratio. Comparing their data with palaeontological, anatomical and biochemical evidence, the authors are inclined to consider G. galloti and L. graeca as the most ancient lizards among those studied and to ascribe L. graeca to the group Lacerta part II together with L. dugesii. P. pityusensis should also be ascribed to the same group on the basis of the result, of this study. The other four species studied (L. lepida, L. trilineata, L. viridis and L. schreiberi) appear to be of fairly recent origin and should be ascribed to the group Lacerta part I, on the basis of the homogeneous distribution of the chromaffin cells inside the adrenal gland and their low NA/A cell ratios.

×

It is currently unclear whether retinal ganglion cell (RGC) axon regeneration depends on down‐regulation of axon growth‐inhibitory proteins, and to what extent outgrowth‐promoting substrates contribute to RGC axon regeneration in reptiles. We performed an immunohistochemical study of the regulation of the axon growth‐inhibiting extracellular matrix molecules tenascin‐R and chondroitin sulphate proteoglycan (CSPG), the axon outgrowth‐promoting extracellular matrix proteins fibronectin and laminin, and the axonal tenascin‐R receptor protein F3/contactin during RGC axon regeneration in the lizard, Gallotia galloti. Tenascin‐R and CSPG were expressed in an extracellular matrix‐, oligodendrocyte/myelin‐ and neuron‐associated pattern and up‐regulated in the regenerating optic pathway. The expression pattern of tenascin‐R was not indicative of a role in channeling or restriction of re‐growing RGC axons. Up‐regulation of fibronectin, laminin, and F3/contactin occurred in spatiotemporal patterns corresponding to tenascin‐R expression. Moreover, we analyzed the influence of substrates containing tenascin‐R, fibronectin, and laminin on outgrowth of regenerating lizard RGC axons. In vitro regeneration of RGC axons was not inhibited by tenascin‐R, and further improved on mixed substrates containing tenascin‐R together with fibronectin or laminin. These results indicate that RGC axon regeneration in Gallotia galloti does not require down‐regulation of tenascin‐R or CSPG. Presence of tenascin‐R is insufficient to prevent RGC axon growth, and concomitant up‐regulation of axon growth‐promoting molecules like fibronectin and laminin may override the effects of neurite growth inhibitors on RGC axon regeneration. Up‐regulation of contactin in RGCs suggests that tenascin‐R may have an instructive function during axon regeneration in the lizard optic pathway.

×

Using anterograde tracing with HRP and antibodies (ABs) against neurofilaments, we show that regrowth of retinal ganglion cell (RGC) axons in the lizard Gallotia galloti commences only 2 months after optic nerve transection (ONS) and continues over at least 9 months. This is unusually long when compared to RGC axon regeneration in fish or amphibians. Following ONS, lizard RGCs up-regulate the immediate early gene C-JUN for 9 months or longer, indicating their reactive state. In keeping with the in vivo data, axon outgrowth from lizard retinal explants is increased above control levels from 6 weeks, reaches its maximum as late as 3 months, and remains elevated for at least 1 year after ONS. By means of BrdU incorporation assays and antiproliferating cell nuclear antigen immunohistochemistry, we show that the late axon outgrowth is not derived from new RGCs that might have arisen in reaction to ONS: no labeled cells were detected in lizard retinas at 0.5, 1, 1.5, 3, 6, and 12 months after ONS. Conversely, numbers of RGCs undergoing apoptosis were too low to be detectable in TUNEL assays at any time after ONS. These results demonstrate that retinal axon regeneration in G. galloti is due to axon regrowth from the resident population of RGCs, which remain in a reactive state over an extended time interval. Neurogenesis does not appear to be involved in RGC axon regrowth in G. galloti.

×

Retinal ganglion cell (RGC) axons in lizards (reptiles) were found to regenerate after optic nerve injury. To determine whether regeneration occurs because the visual pathway has growth-supporting glia cells or whether RGC axons regrow despite the presence of neurite growth-inhibitory components, the substrate properties of lizard optic nerve myelin and of oligodendrocytes were analyzed in vitro, using rat dorsal root ganglion (DRG) neurons. In addition, the response of lizard RGC axons upon contact with rat and reptilian oligodendrocytes or with myelin proteins from the mammalian central nervous system (CNS) was monitored. Lizard optic nerve myelin inhibited extension of rat DRG neurites, and lizard oligodendrocytes elicited DRG growth cone collapse. Both effects were partially reversed by antibody IN-1 against mammalian 35/250 kD neurite growth inhibitors, and IN-1 stained myelinated fiber tracts in the lizard CNS. However, lizard RGC growth cones grew freely across oligodendrocytes from the rat and the reptilian CNS. Mammalian CNS myelin proteins reconstituted into liposomes and added to elongating lizard RGC axons caused at most a transient collapse reaction. Growth cones always recovered within an hour and regrew. Thus, lizard CNS myelin and oligodendrocytes possess nonpermissive substrate properties for DRG neurons—like corresponding structures and cells in the mammalian CNS, including mammalian-like neurite growth inhibitors. Lizard RGC axons, however, appear to be far less sensitive to these inhibitory substrate components and therefore may be able to regenerate through the visual pathway despite the presence of myelin and oligodendrocytes that block growth of DRG neurites.

×

The myelin-associated protein Nogo-A contributes to the failure of axon regeneration in the mammalian CNS. Inhibition of axon growth by Nogo-A is mediated by the Nogo-66 receptor (NgR). Non-mammalian vertebrates, however, are capable of spontaneous CNS axon regeneration, and we have shown that retinal ganglion cell (RGC) axons regenerate in the lizard, Gallotia galloti. Using immunohistochemistry, we observed spatiotemporal regulation of Nogo-A and NgR in cell bodies and axons of RGCs during ontogeny. In the adult lizard, expression of Nogo-A was associated with myelinated axon tracts and up-regulated in oligodendrocytes during RGC axon regeneration. NgR became up-regulated in RGCs following optic nerve injury. In in vitro studies, Nogo-A-Fc failed to inhibit growth of lizard RGC axons. The inhibitor of pkA activity, KT5720 blocked growth of lizard RGC axons on substrates of Nogo-A-Fc, but not laminin. On patterned substrates of Nogo-A-Fc, KT5720 caused restriction of axon growth to areas devoid of Nogo-A-Fc. cAMP levels were elevated over sustained periods in lizard RGCs following optic nerve lesion. We conclude that Nogo-A and NgR are expressed in a mammalian-like pattern and up-regulated following optic nerve injury, but presence of Nogo-A does not inhibit RGC axon regeneration in the lizard visual pathway. The results of outgrowth assays suggest that outgrowth-promoting substrates and activation of the cAMP/pkA signaling pathway play a key role in spontaneous lizard retinal axon regeneration in the presence of Nogo-A. Restriction of axon growth by patterned Nogo-A-Fc substrates suggests that Nogo-A may contribute to axon guidance in the lizard visual system.

×

Während einer Reise im Juni 2016 nach Fuerteventura und eines Ausflugs auf die Insel Lobos wurde die Herpetofauna und Flora beobachtet und fotografiert. Es wurden die hier lebende Unterart der Atlantischen Eidechse, Gallotia atlantica mahoratae sowie die von teneriffa nach Esquinzo verschleppte Gallotia galloti eisentrauti gefunden. Der Purpurarienskink, Chalcides simonyi und die ebenfalls nach Fuerteventura verschleppte Gran-Canatria-Eidechse, Gallotia stehlini wurden leider nicht gefunden.

×

1. Males and females often differ from one another in phenotypic traits due to differential investment in traits relevant to the fitness of each sex. However, how differences in sexually dimorphic traits affect ecologically relevant performance traits and whether these are correlated with variation in ecology remains poorly understood. 2. Here, we test the co-evolution of head shape, bite force capacity and diet in male and female lizards (Gallotia) from the Canary Islands, known to be sexually dimorphic. We collected data on bite force and head size and shape for both sexes of all seven extant species on all seven islands of the archipelago (ten evolutionary-independent lineages). Moreover, we collected diet data for five out of the seven species (eight lineages). 3. Our results show that the evolution of head morphology is associated with the evolution of bite force in both sexes. However, only in females is the evolution of head morphology and bite force associated with the evolution of diet. In males, head morphology and bite force are decoupled from the evolution of diet. In conjunction with the male head shape characterized by a broad rostrum, this suggests that head shape and bite force may be evolving principally under sexual selection in males. 4. Our data thus suggest that head morphology and associated functional traits may evolve under different selective pressures in the two sexes.

×

Comparison of genetic variability between ten populations of Canarian lizards (Gallotia galloti complex) sampled on four islands, shows the existence of two well differentiated lineages. The first one groups the populations from the islands of Hierro and Gomera (G. caesaris) and the second those from the islands of Tenerife and La Palma (G. gallotia s. str.). The analysis of allelic frequencies, the projection of the individuals on the two princepal axes of factorial analysis of correspondences, and the very low viability of offspring support the idea of a differenciation at the specific level between the two lineages (Gallotia galloti s. str. and G. caesaris) and the validity of at least one subspecific taxon per island.

×

Chemosystematic investigations on the position of Lacerta jayakari and the genera Gallotia and Psammodromus (Sauria; Lacertidae) 13 species of the genera Lacerta, Psammodromus and Gallotia (L. erhardii, L. filfolensis, L. bedriagae, L. cappadocica, L. jayakari, L. vivipara, L. trilineata, L. agilis, P. hispanicus, P. algirus, G. atlantica, G. galloti, G. stehlin:) have been examined by means of micro complement fixation tests (albumin) as well as by proteinelectrophoresis concerning 14 genetic loci. The results and their con-sequences are the follows: 1. L. cappadocica, L. bedriagae, and L. erhardii/L. filfolensis are representatives of phylogeneticly equivalent groups (subgenera). Their isolation in the Middle Miocene corresponds with the first contacts of the landmasses of Eurasia and Africa. 2. Lacerta jayakari may be considered as a representative of a further group equivalent in this aspect; though the immunological results would not exclude a position near the green lizards (subgenus Lacerta s. str.). 3. Because of this isolated position of L. jayakari for this species (and Lacerta cyanura) the subgenus Omanosaura subgen. nov. has been established. 4. Psammodromus hispanicus and P. algirus have probably been isolated of each other since the Middle Miocene, too. 5. The radiation of the genus Gallotia corresponds closely with genesis of the Canary Isles.

×

Albumins from several species assigned to Lacerta s. 1. and Gallotia were investigated by means of the Micro-Complement fixation technique. The phylogenetic trees evaluated according to Fitch & Margoliash (1967) and Beverley & Wilson (1982) led us to infer a division, which is in accordance with protein electrophoretic results (Mayer & Tiedemann, 1982) as well as with the subgeneric division used before the studies of Böhme (1971) and Arnold (1973).

×

Gallotia is an endemic genus of Lacertidae from the Canary Islands. This genus is known to be omnivorous. It displays an opportunistic feeding behaviour and feeds on a wide variety of food with an important part made of plant matters, including stems, leaves, flowers and fruits. Its diet includes arthropods, other lizards, various animal carrions and even human leftover food too. Two species among the genus Gallotia have been reported to practice coprophagy. Here, the authors share personal observations of this behaviour in three other species of the same genus.

×

Oceanic island ecosystems harbour many endemic plant and animal species, which are often threatened because they have only a few small populations. Many factors contribute to the biological viability of such populations, such as demography and population dynamics, breeding system and pollination ecology, seed dispersal and genetic variation. In a collaborative project, all these factors were studied in the rare endemic, predominantly monoecious shrub Bencomia exstipulata Svent. (Rosaceae), which grows exclusively in the national parks of El Teide (Tenerife) and La Caldera de Taburiente (La Palma). Demography was monitored through annual censuses of individual plants in a natural and an augmented population on Tenerife. The breeding system and reproductive success were studied through bagging and pollination experiments, and insect visitation censuses. Seed dispersal by animals was assessed using cafetaria experiments. With matrix projection models and stochastic simulations, we show that the Tenerife population was demographically stable. This was largely explainable by the high survival of adult individuals. Despite frequent germination, successful seedling recruitment was very rare. Male and female flowers occurred in separate inflorescences within individuals, although some inflorescences were mixed and some shrubs were entirely male or female. Despite frequent visits by honeybees, the species is predominantly wind pollinated. Insect-proof bags reduced seed set by 12.5%, and pollen-proof bags by 44%. Large quantities of airborne pollen were detected on unbagged sticky microscope slides, this was 56% reduced by insect-proof and 96% by pollen-proof bags. Hence, some self-pollination also seems to occur. Cafetaria experiments showed that the local lizards (Gallotia galloti Oudart) readily eat the fruits and that the seeds pass through their intestines unharmed and germinable. Since other dispersal vectors are unknown, saurochory seems the most likely mode of dispersal. Our study strongly suggests that the population of B. exstipulata on Tenerife is viable, and that there are no significant threats associated with its breeding system, pollination or seed dispersal. To alleviate the natural extinction risk typical of narrow endemics, five main conservation measures are proposed.

×

Gold-toned bipyramidal neurons of the dorsomedial cortex of Lacerta have been studied using light and electron microscopy. The spines have been classified as stubby, mushroom-shaped or thin. Thin and mushroomshaped spines are only found on proximal and intermediate dendritic segments, whereas stubby spines are found on distal dendritic segments. A Timm`s method modification for electron microscopy (sulphide-osmium procedure) has been used. Timm-positive axonal endings usually synapse on thin and mushroomshaped spines, whereas Timm-negative axonal endings usually synapse on stubby spines. Timm-positive afferents and their post-synaptic spines on bipyramidal neurons of Lacerta`s dorsomedial cortex are compared with the corresponding elements on pyramidal neurons of the CA3 region of the hippocampus of mammals, on the basis of several histochemical and morphological studies. The possibility that these two neuronal types may be homologous is discussed.

×

Gallotia galloti lizards as poikilotherms organisms, depend on the external environment to regulate its body temperature. Changes in environmental temperature are reflected in the heart rate, demonstrating a direct and exponential relation established from the study of the electrocardiogram (EKG). Moreover, heart rate is controlled by the autonomic nervous system. Studies have proved this by using blockers, which effects are reflected on the heart rate variability (HRV) signal obtained from the EKG. The hypothesis of this study was to analyse the effects of increasing environmental temperature could have on heart rate by studying the HRV signal. The results obtained in the time domain analysis allows to prove an increase in heartrate and an increase in the distance between RR intervals as well as the environmental temperature increases, showing the existence of an indirect relationship between these two parameters. Nonlinear analysis results show a decrease in the complexity of the function as the environmental temperature increases. The other parameters have not shown any statistical differences, therefore no conclusions can be established of the frequency domain analysis, representing the SNA activity.

×

In search for the final host of Sarcocystis gallotiae, sarcocysts of naturally infected Canarian lizards, Gallotia galloti, were fed to vertebrate predators of the lizard. Repeated transmission experiments remained negative. Routine check of the feces of the wild G. galloti revealed shedding of sporocysts. The sporocysts were administered to small vertebrates, which may function as prey for G. galloti. The transmission experiments remained negative. The observation of a high intraspecific aggression of G. galloti, including cannibalism and autotomy, seemed to support the hypothesis that this behavior might be the base of a an unexpected predator-prey relationship. Sarcocysts of S. gallotiae, fed to two laboratory-bred G. galloti resulted in excretion of sporulated sporocysts measuring 9.7 (9.2–12.2)×7.7 (6.6–9.2) Μm. Oral inoculation of two laboratory-bred G. galloti with experimentally gained sporocysts, led to the development of sarcocysts of 150–200 Μm in length and 80–110 Μm in width in the musculature of the lizards 153 days p.i. The sarcocysts were identified as S. gallotiae by light and electron microscopy. In epithelial cells of the intestine of G. galloti, which had experimentally been infected with sarcocysts of S. gallotiae, stages of gamogony and sporogony were found. We suggest that the life cycle of S. gallotiae is monoxenous and not obligatorily heteroxenous. The genus Sarcocystis seems to be more flexible in its biologic adaptability to utilize autotomy and cannibalism for completing its cycle than had heretofore been assumed.

×

All recent members of the genus Gallotia from the seven large isles of the Canary Archipelago have been investigated immunologically by means of micro-complement- fixation technique. Three species of genera living in NW-Africa were used as outgroup. Prom the evolutionary tree constructed from the results isolation times can be estimated and ways of colonization can be reconstructed. Various possibilities of insertion of the fossil species G . goliath in the evolutionary tree are discussed.

×

The family Lacertidae encompasses more than 250 species distributed in the Palearctis, Ethiopis and Orientalis. Lacertids have been subjected in the past to several morphological and molecular studies to establish their phylogeny. However, the problems of convergent adaptation in morphology and of excessively variable molecular markers have hampered the establishment of well supported deeper phylogenetic relationships. Particularly the adaptations to xeric environments have often been used to establish a scenario for the origin and radiation of major lineages within lacertids. Here we present a molecular phylogenetic study based on two nuclear marker genes and representatives of 37 lacertid genera and distinct species groups (as in the case of the collective genus Lacerta). Roughly 1600 bp of the nuclear rag1 and c-mos genes were sequenced and analyzed. While the results provide good support to the hitherto suggested main subfamilies of Gallotiinae (Gallotia and Psammodromus), Eremiainae and Lacertinae [Harris, D.J., Arnold, E.N., Thomas, R.H., 1998. Relationships of lacertid lizards (Reptilia: Lacertidae) estimated from mitochondrial DNA sequences and morphology. Proc. R. Soc. Lond. B 265, 1939–1948], they also suggest unexpected relationships. In particular, the oriental genus Takydromus, previously considered the sister-group to the three subfamilies, is nested within Lacertinae. Moreover, the genera within the Eremiainae are further divided into two groups, roughly corresponding to their respective geographical distributions in the Ethiopian and the Saharo-Eurasian ranges. The results support an independent origin of adaptations to xeric conditions in different subfamilies. The relationships within the subfamily Lacertinae could not be resolved with the markers used. The species groups of the collective genus Lacerta show a bush-like topology in the inferred Bayesian tree, suggesting rapid radiation. The composition of the subfamilies Eremiainae and Lacertinae as well as their phylogeography are discussed.

×

We present data to confirm that the island of La Palma harbours the first established feral population of ferrets Mustela furo on the Canary Islands in the Atlantic Ocean. It is not known when the species was introduced but individuals occasionally lost during hunting appear to have become established sometime in the previous 2 decades. Sightings of ferrets are mainly in the north of the island but they are likely to expand their range southwards, and a few have already been detected in the centre of the island. We report a total of 45 cases of wild ferrets in 28 different localities during 1998–2007. To minimize effects on native species, control measures or eradication are required. Public awareness of the problem and education campaigns, especially among hunters, are needed to reduce the threat of this alien species to the biota of the Canary Islands.

×

The distribution of neuropeptide Y (NPY)-like immunoreactivity was studied in the brain of the lizard Gallotia galloti, in order to gain insight into the comparative topography of this peptide. Antisera against both NPY and its C-terminal flanking peptide (C-PON) were used, demonstrating a general coexistence of both peptides, as described in other vertebrates. Most NPY-like immunoreactive (NPY-LI) cell bodies were observed in the telencephalon, specifically in various olfactory structures, all cortices, septum, basal ganglia (except for the globus pallidus), the nucleus of the diagonal band of Broca, the amygdaloid complex, and the bed nucleus of the anterior commissure. NPY-LI cells were also seen in the preoptic and hypothalamic regions and the dorsal thalamus (mainly in the perirotundal belt), as well as in the mesencephalic tegmentum (in the ventral tegmental area, the substantia nigra, and the retrorubral area). NPY-LI fibers and terminals were widely distributed in the brain. All visual and auditory neuropiles were densely innervated. Specially dense plexuses were seen in the nucleus accumbens, the ventral pallidum, the suprachiasmatic and ventromedial hypothalamic nuclei, the nucleus medialis thalami, the left habenula, and the central nucleus of the torus semicircularis. Our analysis shows that the distribution of NPY-like immunoreactivity in the forebrain of Gallotia largely resembles that of other vertebrates, whereas differences are mainly observed in the brainstem. The widespread distribution of NPY in the lizard brain suggests several modulatory functional roles, either in local-circuit systems of the forebrain, or in various limbic, neuroendocrine, and sensory pathways.

×

For a better insight into general and derived traits of developmental aspects of catecholaminergic (CA) systems in amniotes, we have studied the development of these systems in the brain of a lizard, Gallotia galloti, with tyrosine hydroxylase (TH)- and dopamine (DA) immunohistochemical techniques. Two main groups of TH-immunoreactive (THi) perikarya appear very early in development: one group in the midbrain which gives rise to the future ventral tegmental area, substantia nigra and retrorubral cell groups, and another group in the tuberomammillary hypothalamus. Somewhat later in development, TH/DA-immunoreactive cells are observed in the thalamus, rostrodorsal hypothalamus and spinal cord, and, with another delay, in the suprachiasmatic nucleus, the periventricular organ, and the pretectal posterodorsal nucleus. CA cell groups that appear rather late in development include the cells in the olfactory bulb, the locus coeruleus and the caudal brainstem. As expected, the development of immunoreactive fibers stays behind that of the cell bodies, but reaches the adult-like pattern just prior to hatching. The present study revealed considerable variation in the relation between the state of cytodifferentiation and first expression of TH/DA immunoreactivity between CA cell groups. Catecholamine cells in the midbrain and tuberomammillary hypothalamus are still migrating, immature (absence of dendrites) and express only TH immunoreactivity at the time of first detection. Cells which appear at later developmental stages lie already further away from the ventricle, possess two or more dendritic processes, and generally express both TH- and DA immunoreactivity.

×

In order to study the relationship between retinal projections and immunohistochemically identified neurotransmitter systems in the primary visual centers of the brain in lizards, intraocular injections of horseradish peroxidase were combined with immunohistochemistry. Antibodies raised against six substances were applied: choline acetyltransferase (ChAT), serotonin (5-HT), tyrosine hydroxylase (TH), dopamine (DA), substance P (SP), and leu-enkephalin (LENK). In the primary visual centers of the lizards Gekko gecko and Gallotia galloti, notable overlap was observed between retinofugal fibers with: 1) ChAT-immunoreactive fibers in almost all primary visual centers; 2) 5-HT-immuno-reactive fibers in the ventral lateral geniculate body and the basal optic nucleus; 3) TH-immunoreactive fibers in the nucleus ovalis and the dorsal lateral geniculate body; 4) SP- and LENK-immunoreactive fibers in the perirotundal belt; and 5) TH- and SP-immunoreactive fibers in the pretectal posterodorsal nucleus. The latter nucleus also contains dopaminergic cell bodies that lie outside the retinal target area but have dendrites extending into it. Several differences were noted in the distribution of 5-HT-, TH-, DA-, and LENK-immunoreactive fibers in the tectum of the midbrain in the two species studied. Distinct laminae of 5-HT-immunoreactive fibers (layer 9) and TH- and DA-immunoreactive fibers (layers 9 and 11) are present in G. gecko but absent or, at least, less distinct in G. galloti. On the contrary, the optic layers in the tectum of G. galloti show a rather dense plexus of LENK immunoreactive fibers, whereas the corresponding layers in G. gecko are devoid of LENK-immunoreactivity. Since only a very few ChAT immunoreactive fibers were observed in the optic nerve of G. galloti, most of the observed immunoreactive fibers in the primary visual centers are considered to have an extraretinal origin. Putative sources of the cholinergic, the monoaminergic, and the peptidergic innervation of the primary visual centers in reptiles include the isthmic nucleus, the raphe nuclei, the substantia nigra and the nucleus of the posterior commissure, as reported in other amniotes.

×

The aim of the present study is to provide a complete description of the distribution of Choline acetyltransferase (ChAT) immunoreactivity (i) in the brain of the lizard Gallotia galloti, on the basis of two different primary antisera: rat anti-ChAT and rabbit anti-chicken CUT. Considering that the brain is a segmented structure, we have analysed our data with respect to transverse segmental domains (or neuromeres), which have been previously described by several authors in the brain of vertebrates. In the telencephalon, ChATi neurons are seen in the cortex, anterior dorsal ventricular ridge, basal ganglia, diagonal band, and bed nucleus of the stria terminalis. Further caudally, ChATi cell bodies are located in the preoptic area, hypothalamus, habenula, isthmus, and all motor efferent centers of the brainstem and spinal cord. Plexuses of ChATi fibers are observed in the areas containing cholinergic cell bodies. In addition, distinct plexuses are found in the cortex, the posterior dorsal ventricular ridge, the neuropiles of all primary visual centers of the diencephalon and mesencephalon, and several non-visual nuclei of the brainstem. The distribution of ChAT immunoreactivity in the brain of G. galloti resembles in many respects that of other vertebrates, and differences are mainly observed in the pretectum and midbrain tectum. Transverse segmental domains were identified in the brainstem and forebrain of Gallotia when the cranial nerve roots and fiber tracts were used as a reference, and most cranial motor nuclei were found to occupy the same segmental positions as have been reported in the chick.

×

In a Golgi study of the area triangularis (AT), a rostral nucleus of the ventral thalamus of Gallotiagalloti, we have identified four major neuronal types on the basis of their morphological characteristics: medium-sized fusiforms with two processes, medium-sized fusiforms with three or four processes, small bipolars, and small and medium-sized multipolars. These neurons are characterized by a simple morphology and radial arrangement. Cell size varies from small to medium, and all axons project laterally. These characteristics distinguish AT neurons from those of neighboring nuclei. In addition, we found some evidence of differential topographic distribution of each neuronal type within the nucleus. Medium-sized fusiform neurons with two processes are located in the most ventral part, where they constitute the ventral nuclear limit. Small multipolar neurons prevail in the dorsal and ventromedial parts, and in the rest of the nucleus medium-sized neurons, including both fusiform with three or four processes and multipolar types, are normally found. Finally, we discuss a putative homology of the reptilian AT with a part of the mammalian zona incerta.

×

Anthropization of insular ecosystems may have negative impacts on native populations of lizards, which provide core ecosystem services on islands. We aimed to identify environmental factors to explain the interlocal variation in faecal glucocorticoids, parasite intensity, and body condition in populations of insular lizards. A cross-sectional design during the summer of 2017 and 2018 was used to sample 611 adult lizards, Gallotia galloti. Interlocal variation of three stress indicators was analysed in response to environmental variables across a wide environmental gradient in Tenerife (Canary Islands): (i) concentration of faecal glucocorticoids, (ii) intensities of infection by hematic parasites, and (iii) body condition. The data, with low spatial autocorrelation, were analysed using multimodel inference and model cross-validation. Bioclimatic variables associated with the extreme hot and dry climate of summer were the most informative predictors. Interlocal variation in faecal corticosterone in males was best fitted to a model that included the maximum temperature of the warmest month, although the best predictor was habitat anthropization. The thermal annual range, associated with extreme thermal events, was positively related to faecal corticosterone in females. Extreme hot temperatures were positively related to the median parasite intensities in both sexes, while the highest mean intensities of infection were found in females from the most xeric coastal localities. None of the predictors tested, including faecal glucocorticoids, explained individual or interlocal variation in body condition. Effects of human pressure and climate change on insular populations of lizards can be additive. However, the uncoupled relationship found between body condition and the faecal glucocorticoid content suggests that current negative effects may be aggravated during drought periods in summer. Given the impact of climate change on islands, our results may be of application to other archipelagos, where lizards also play key ecological roles.

×

The genus Karyolysus was originally proposed to accommodate blood parasites of lacertid lizards in Western Europe. However, recent phylogenetic analyses suggested an inconclusive taxonomic position of these parasites of the order Adeleorina based on the available genetic information. Inconsistencies between molecular phylogeny, morphology, and/or life cycles can reflect lack of enough genetic information of the target group. We therefore surveyed 28 localities and collected blood samples from 828 lizards of 23 species including lacertids, skinks, and geckoes in the western Mediterranean, North Africa, and Macaronesia, where species of Karyolysus and other adeleorine parasites have been described. We combined molecular and microscopic methods to analyze the samples, including those from the host type species and the type locality of Karyolysus bicapsulatus. The phylogenetic relationship of these parasites was analyzed based on the 18S rRNA gene and the co-phylogenetic relationship with their vertebrate hosts was reconstructed. We molecularly detected adeleorine parasites in 37.9% of the blood samples and found 22 new parasite haplotypes. A phylogenetic reconstruction with 132 sequences indicated that 20 of the newly detected haplotypes clustered in a well-supported clade with another 18 sequences that included Karyolysus galloti and Karyolysus lacazei. Morphological evidence also supported that K. bicapsulatus clustered in this monophyletic clade. These results supported the taxonomic validity of the genus. In addition, we found some parasite haplotypes that infected different lizard host genera with ancient diverging histories, which suggested that Karyolysus is less host-specific than other blood parasites of lizards in the region. A co-phylogenetic analysis supported this interpretation because no significant co-speciation signal was shown between Karyolysus and lizard hosts.

×

Pigment-based ornaments in vertebrates may reflect the body condition or health status of the individual in correlation with environmental stress and hormonal balance. Among the environmental factors shaping sexual colouration, parasitic infections have been stressed as an important evolutionary pressure constraining the maintenance of pigment-based ornaments. However, the honesty of structure-based ornaments in vertebrates is still under debate. Structural UV-biased ornaments in Gallotia lizards were described as a trait used by conspecifics during mate and rival assessment suggesting the reliability of these signals. We investigated the relationship between parasitaemia, body condition and a structural-based ornament present in the cheek of the sexually dichromatic Canarian lacertid Gallotia galloti in a population with an almost 100 % prevalence of haemoparasites. Using spectrophotometric techniques, we found that males with higher values of cheek UV chroma were infected with more haemoparasites. No significant relationship was found between haemoparasite load and body condition. However, males with higher cheek UV chroma showed significantly better body condition. In addition, we found that cheek hue was significantly related to body condition of individuals in both sexes. In males, cheek reflectivity biased towards the UV range was significantly related to better body condition. In females, those individuals with better body condition showed more whitish cheeks with less UV suggesting that cheek hue serves as an intersexual signal for sex recognition. We conclude that the positive relationship between cheek chroma and parasite load in male lizards is compatible with both differential density of melanin and iridophore arrangement in the dermis conveying an individual’s ability to cope with environmental stress.

×

Host abundance might favour the maintenance of a high phylogenetic diversity of some parasites via rapid transmission rates. Blood parasites of insular lizards represent a good model to test this hypothesis because these parasites can be particularly prevalent in islands and host lizards highly abundant. We applied deep amplicon sequencing and analysed environmental predictors of blood parasite prevalence and phylogenetic diversity in the endemic lizard Gallotia galloti across 24 localities on Tenerife, an island in the Canary archipelago that has experienced increasing warming and drought in recent years. Parasite prevalence assessed by microscopy was over 94%, and a higher proportion of infected lizards was found in warmer and drier locations. A total of 33 different 18s rRNA parasite haplotypes were identified, and the phylogenetic analyses indicated that they belong to two genera of Adeleorina (Apicomplexa: Coccidia), with Karyolysus as the dominant genus. The most important predictor of betweenlocality variation in parasite phylogenetic diversity was the abundance of lizard hosts. We conclude that a combination of climatic and host demographic factors associated with an insular syndrome may be favouring a rapid transmission of blood parasites among lizards on Tenerife, which may favour the maintenance of a high phylogenetic diversity of parasites.

×

Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

×

Aim Temperature influences most components of animal ecology and life history – but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location World-wide. Methods We used a large (861 species) global dataset of lizard body temperatures, and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures.We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity. Main conclusions Lizards with low body temperatures do not seem to have ‘slower’ life-history attributes than species with high body temperatures. The longer seasons prevalent in warm regions, and physiological processes that operate while lizards are inactive (but warm enough), make environmental temperatures better predictors of lizard life-history variation than body temperatures. This surprisingly greater effect of environmental temperatures on lizard life histories hints that global warming may have a profound influence on lizard ecology and evolution.

×

This note describes general patterns of winter activity in lizard populations along a latitudinal gradient with an approximate range of twelve degrees (26 to 38°N) in southern Europe and North Africa. We make use of qualitative data gathered through the last ten years in the area, as well as much more accurate quantitative data obtained from periodic censuses covering the whole year cicle in certain populations. Results allow us to impute a great importance to the activity observed in the unfavourable season. This activity seems to be an attribute at the population level and shows a great variability between and within species and populations.

×

s wurde das Verhalten einer Eidechsenpopulation in dem Gebiet von Buenavista (NO Teneriffa) untersucht, und zwar mit dem Ziele, raum-zeitliche Aspekte des Verhaltens zu klären. Ein Rechteck von 352 m² wurde dort abgesteckt und darauf ein Gitternetz aus Stäben in Abständen von 2 m gesetzt, um das Verhalten mit dem jeweiligen Standort in Verbindung bringen zu können. Von dem Versteck aus wurde in den Monaten April, Mai, Juni jeweils an zwei Tagen jede Woche beobachtet, und der Wandel der Verhaltensweisen sowie die Benutzung des Raumes durch die Einzelexemplare registriert. Die Aktivität begann in den Morgenstunden und trat in folgender chronologischer Reihenfolge auf: Sonnen- und Erkundungsverhalten, Aggression und Balz. Um die Mittagszeit ließ die Aktivität nach. Die Einzugsgebiete hatten eine errechnete Ausdehnung von 15 bis 89 m² bei den ♂ und 22,4 bis 77,7m² bei den ♀. In allen Fällen überlappten sich die Bereiche der einzelnen Individuen. Obgleich wahrscheinlich keine Individuenreviere vorhanden sind, wurden doch einzelne Plätze gegen Eindringlinge verteidigt.

×

Several behaviour patterns that appear during courting of females by male lizards are described for two different Canarian subspecies: Gallotia galloti eisentrauti and G. galloti palmae. A report of copulation in G.galloti caesaris is also included. The importance of the courting behaviour as a character for studying behaviour evolution and taxonomic relationships is discussed in relation to another behavioural character previously cited by other authors.

×

From the study of behaviour of the lizard Gallotia galloti in a natural population of the Northwest of Tenerife (Canary Islands) some behaviour patterns, which had not been previously discovered could be described in detail. The lizards were observed through binoculars from a hide during several days per week of April, May and June. The actual sequence of behaviour patterns was verbally recorded on a microcasette and those that were discovered for the first time were carefully described using the “by consequence” criterion and considering behaviour as a series of discrete events. The presently described behaviour patterns contribute to enlarge the behavioural catalogue of the studied species and some of them are cited as lacertid lizards for the first time. The possible function of the patterns is also discussed.

×

The alimentary habits of lizard specimens are described from behavioral observations of a natural population of the species Gallotia galloti. The spatial and temporal distribution of eating behaviours in the studies specimens were also analysid for a selected area of 352 m². The results showed that the cited population had a mainly vegetable diet, principally Opuntia fruits and Launaea arborescens flowers, although it also fed on some insects. On the other hand, the temporal distribution of different eating behaviours was influenced by the weather, being more sommon in hours near middaxy. Overlapping spatial distribution of eating behaviours for the different animals was observed.

×

In order to contribute to a comparative view on lacertids, the effect of pinealectomy on the freerunning activity displayed under constant darkness and temperature (27.5°C ± 0.5) has been studied in the lizard Gallotia galloti eisentrauti. Animals showed an entrained motor activity rhythm under an initial light-dark (12:12 hours) routine and freerunning circadian periods ranging between 24.1 and 25.5 h during constant darkness (periodograms obtained by Sokolove & Bushell`s method). After pinealectomy, most animals showed no significant circadian rhythm, their locomotor activity becoming diffuse throughout the whole 24 h period. Thus, the pineal gland seems to play an important role as a main pacemaker regulating the endogenous activity rhythm under constant conditions. This result contrasts with that found in Podarcis sicula where after pinealectomy only changes in length of the freerunning period were found.

×

Within and between-population variation differences in size andcolor pattern traits are described for the lizards Gallotia galloti eisentrauti and G. g. galloti from two different habitats. For males, snout-vent length (SVL), head length (HL), cheek mark length (CML), and the number of ventral patches (NVP) were all greater in G. g. eisentrauti. The first lateral patch (FLPL) was longer in males of G. g. galloti but the number of lateral blue patches (NLBP) did not differ. Considering all traits, male CML and FLPL had the greatest coefficients of variation in both races. Snout-vent length and HL were greater in G. g. eisentrauti females than in G. g. galloti females, while the opposite occurred for NLBO and NVP. Adult male to adult female SVL ratio, a measure of body size dimorphism, was 1.19 for G. g. eisentrauti and 1.21 for G. g. galloti. For most animals. Lateral patch color was in the 5 PB (purple-blue) step of the Munsell System Chart, and value and chroma were 3-4 and 6, respectively. ANCOVA of the HL-SVL relationship showed a significant difference between male and female HL in both races; this difference may reflect differences in HL growth. The data are discussed in relation to information on male intrasexual competition.

×

This study describes the sequence of behaviour during aggressive encounters between male ‘tizón’ lizards (G. galloti galloti) and assesses the effect of morphological and behavioural traits on the outcome and intensity of staged aggressive encounters between males. Aggressive encounters ranged from only throat extension to escalated fights with biting and rolling over. Winners were heavier, had longer heads, and performed tongue-flicking, throat extension and biting at a higher rate than losers. The rate of aggressive behaviour increased with decreasing difference in snout-to-vent length, head length and head width of the contestants. The results are in agreement with some predictions of the sequential assessment game model in that probability of victory increased with the difference in fighting ability and that the rate of aggressive behaviour was higher in contests between animals of similar size.

×

The aim was to study as to how biometric and life-history traits of endemic lacertids in the Canary Islands (genus Gallotia) may have evolved, and possible factors affecting the diversification process of this taxon on successively appearing islands have been deduced. To that end, comparative analyses of sexual dimorphism and scaling of different body, head and life-history traits to body size in 10 species/subspecies of Gallotia have been carried out. Both Felsenstein`s independent contrasts and Huey and Bennett`s `minimum evolution` analyses show that male and female snout-vent length (SVL) changed proportionally (sexual size dimorphism not changing with body size) throughout the evolution of these lizards and all within-sex biometric traits have changed proportionally to SVL. Life-history traits (size at sexual maturity, clutch size, hatchling SVL and mass, and life span) are highly correlated with adult female body size, the first two being the only traits with a positive allometry to female SVL. These results, together with the finding that the slope of hatchling SVL to female SVL regression was lower than that of SVL at maturity to female SVL, indicates that larger females reach maturity at a larger size, have larger clutches and, at the same time, have relatively smaller hatchlings than smaller females. There was no significant correlation between any pair of life-history traits after statistically removing the effect of body size. As most traits changed proportionally to SVL, the major evolutionary change has been that of body size (a ca. threefold change between the largest and the smallest species), that is suggested to be the effect of variable ecological conditions faced by founder lizards in each island.

×

The temporal and spatial distribution of various aggressive and courting behaviors of the lacertid lizardGallotia galloti was studied in Tenerife (the Canary Islands) for several days from April to June, by direct observations with binoculars from a hide situated near the study area. Aggressive behaviors were exhibited by the lizards throughout the whole recording period and were more frequently shown on sunny days or near the midday hours of cloudy days. The same occurred for courting behaviors, but these were less frequently seen in April and May. The spatial distribution of both kinds of behaviors for each lizard proved to be overlapped, thus confirming the non-territoriality of this lizard population.

×

Sex and population differences in the ultraviolet (UV) reflectance patterns of two phenotypically divergent lacertids from Tenerife, Gallotia galloti eisentrauti and G. g. galloti, are described. Adults in both populations have rows of lateral and ventro-lateral blue patches on either side of the trunk that show a single peak of reflectance in the near UV. The lateral patches of males are more intensely reflective than those of females, but females have more chromatic and UV-shifted lateral patches than males. Most G. g. eisentrauti and some G. g. galloti also have blue cheek patches on either side of the gular area. Male cheek patches have reflectance peaks in the near UV, whereas those of females peak in the visible part of the spectrum. The lateral patches of males from the two populations differ in hue but not in intensity, those of G. g. galloti being more UV-shifted than those of G. g. eisentrauti. Female G. g. galloti have more intensely reflective lateral patches than female G. g. eisentrauti. Interindividual variation in peak wavelength and/or UV chroma is present in both sexes and populations. This is the first demonstration of sexual dichromatism in the UV reflectance of colour patches in a lacertid.

×

Activity data from two experimental lizard groups were analysed in order to search for 24 h‐entrained and ultradian periodicities. The data of a first group were obtained through motion sensitive platforms situated under the animals’ cage and continuously for up to 12 consecutive days; those from a second group were collected by manual recording of the behaviour patterns of individual animals for 2 h each day over a 10‐day period. Lizards from both groups were situated in cages inside isolated chambers in which a light‐dark cycle (12:12), a temperature of 28°C ±1° and a relative humidity of 50–60% were maintained. Periodogram analysis showed the existence of a significant period peak (p < 0.01) at 24 h. Autocorrelation functions and spectral analysis of different data‐segment lengths showed that ultradian periodicities were present in the daily motor activity, appearing as noisy though frequency‐band limited. Differences in the frequency band‐limited fluctuations were found between morning and afternoon activities: during the morning ultradian activity appears distributed in two bands (4.5–36 c/day and 63–94 c/day), the power being mainly concentrated in the second one, while during the afternoon it was in the 4.5–36 c/day band. Results from the second lizard group showed only one band (24–60 c/day) overlapped with the first one from the latter group. Although activity recording methods and some experimental conditions are discussed as possible sources of these differences, the possibility of endogenous ultradian variation within the individuals is also suggested.

×

The distribution of glial fibrillary acidic protein (GFAP)- and vimentin-containing cells was studied by immunohistochemistry in the midbrain of the lizard Gallotia galloti. At embryonic stage 32 (E32), vimentin immunoreactivity appeared first in cell bodies located in the ventricular walls, in radial fibers, and subpial end-feet and increased in these structures until E34E35. Faint GFAP immunoreactivity gradually appeared in the same structures between E34 and E37, and this increased until adulthood, whereas vimentin immunoreactivity decreased after E35, becoming limited to a few end-feet and fibers in the adult, mainly in the tegmentum. Thus, in developing Gallotia midbrain a shift from vimentin-containing to GFAP-containing intermediate filaments begins around E36 or E37. At E40, in addition to the cell bodies in the ependymal area, dispersed GFAP-positive cells, possibly immature astrocytes appeared. These cells showed the same shift. In the adult lizard, GFAP-positive radial glia are still present and coexist with GFAP-positive astrocytes, which are prefentially located in the marginal optic tract and the oculomotor nuclei, but are absent in the fasciculus longitudinalis medialis. Optic tectum, pretectum, tegmentum, and isthmic nuclei are the areas richest in GFAP-positive radial fibers: these were much less abundant in the deep mesencephalic nuclei. Thus, in this lizard, GFAP-positive astrocytes display a clear cut regional distribution: they are present in mesencephalon, whereas they are absent in telencephalon.

×

The immunohistochemical localization of glutamine synthetase, an astrocyte marker in mammals, was determined in the telencephalon and mesencephalon of the lizard Gallotia galloti during development by using an antiserum raised against chicken brain glutamine synthetase. Ependymal glial cells and their radial processes were glutamine synthetase immunoreactive, and they were present also in the adult. Immunoreactivity was also detected in two populations of scattered cell bodies, each preferentially localized in different zones: star-shaped cells morphologically similar to mammalian astrocytes, and ovoid or pear-shaped cell bodies, the processes of which were aligned with radial fibers and formed perivascular end-feet. Both populations displayed ultrastructural characteristics of astrocytes even though a comparison with our previous results (Monzon-Mayoret al., 1989; Yanes et al., 1989) indicated that many of these cells did not react with antibodies directed against the astrocyte-specificglial fibrillary acidic protein. During ontogeny, glutamine synthetase immunoreactivity appeared in radial glial processes and in ependymal glial cells of midbrain at embryonic stage 35 (E35) and of telencephalon at E37; in both regions, immunoreactivity in the radial glia increased until hatching and then decreased until adulthood, but it did not disappear. Labelled scattered cells became progressively more numerous and more immunoreactive. A comparative analysis of the distribution of these cells at different ages tends to suggest that some of the “ovoid astrocytes originate in, and migrate out from, the proliferative zone of the different sulci, whereas the star-shaped cells appear directly in situ, probably because they begin to express glutamine synthetase after they have reached their final location.

×

Canary island lizards are very aggresive animals. h is impossible to keep more than one couple in a terrarium. Kept indoors the lizards arc very shy. Adult animals lose their shyness in an outdoor ter- rarium. If kept together the young animals may fight or even kill each other. My conclusion is to keep the juveniles in separate containers. The fe- males lay about seven eggs in July, and at an incu- bation temperature of 28 to 31o C the eggs hatch after 63 to 68 days.

×

The successful regrowth of retinal ganglion cell (RGC) axons after optic nerve (ON) axotomy in Gallotia galloti indicates a permissive role of the glial environment. We have characterised the astroglial lineage of the lizard optic pathway throughout its ontogeny (embryonic stage 30 [E30] to adults) by using electron microscopy and immunohistochemistry to detect the proliferation marker PCNA (proliferating cell nuclear antigen), the transcription factor Pax2 and the gliofilament proteins vimentin (Vim) and GFAP (glial fibrillary acidic protein). PCNA+ cells were abundant until E39, with GFAP+/PCNA+ astrocytes being observed between E37 and hatching. Proliferation diminished markedly afterwards, being undetectable in the adult optic pathway. Müller glia of the central retina expressed Pax2 from E37 and their endfeet accumulated Vim from E33 and GFAP from E37 onwards. Astrocytes were absent in the avascular lizard retina, whereas abundant Pax2+ astrocytes were observed in the ON from E30. A major subpopulation of these astrocytes coexpressed Vim from E35 and also GFAP from E37 onwards; thus the majority of mature astrocytes coexpressed Pax2/Vim/GFAP. The astrocytes were ultrastructurally identified by their gliofilaments, microtubules, dense bodies, desmosomes and glycogen granules, which preferentially accumulated in cell processes. Astrocytes in the adult ON coexpressed both gliofilaments and presented desmosomes indicating a reinforcement of the ON structure; this is physiologically necessary for local adaptation to mechanical forces linked to eye movement. We suggest that astrocytes forming this structural scaffold facilitate the regrowth of RGCs after ON transection.

×

Lacertid and amphisbaenian lizards are two squamate reptile lineages very divergent morphologically. In fact, adaptation to burrowing deeply modified amphisbaenian worm-like body. Lacertids instead have a typical reptile morphology with a long tail and four well-developed limbs. Despite so different in appearance, they are evolutionarily very close as evidenced by molecular phylogenetic approaches. Consistently, a slow-evolving satellite DNA (IMO-TaqI) described in lacertid lizards was isolated from the genome of the amphisbaenian Trogonophis wiegmanni too. Comparison with lacertid repeats evidenced great similarity, highlighting that molecular characters appeared very suitable especially when morphology is subjected to strong selective pressures.

×

In this paper, we present the first record of the presence of a young Gallotia galloti (F. Lacertidae) inside a stomach of Rana perezi (F. Ranidae).

×

In this paper we present the regression analysis between SVL and eight osteological variables in G. atlantica and G. galloti. Positive significant relationships can be observed among them, although coefficient of determination (R²) indicate better fits in the case of G. galloti than G. atlantica. Furthermore, preliminary data on the weight-length relationships are shown. The proposed models can be used in predator vertebrate alimentary studies that include lizards size selection of both mentioned species and also in paleontological surveys.

×

Body temperature is the most important physiological variable for ectotherms, because it directly affects their biological adequacy through the effect on the performance of variable behavioral and physiological variables (Huey 1982, Huey & Kingsolver 1989, Angilletta et al.2002). The behavior plays a preponderant role in the thermoregulation, allowing a quick and economic adaptation to the spatial and temporal variability of the availability of thermal resources, making it possible to increase / decrease the heat loss / gain by solar radiation, convection and / or conduction (Templeton 1970). The physiological thermoregulation is a mechanism that focuses mainly on variations in the cardiovascular system, where the rate of heat transfer between different parts of the body is modified by changes in heart rate, respiration, blood flow and redistribution (Bartholomew 1982, Seebacher 2000, Dzialowski & O´connor 2001). In this study we wanted to verify the effects produced in the Gallotia galloti by a controlled change of temperature on brain activity, heart rate, respiratory rate and, by means of a photothermal camera, the temperature difference between the head and body of the animal. The results obtained by the analysis in the time domain have been able to verify that the temperature affects the respiratory and cardiac frequency, producing a decrease in the amplitude between the RR and SS peaks. Also, by means of the photographs taken with the photothermal camera, it has been observed that these animals have a thermoregulation system by which they modify the body temperature, including a countercurrent system in the head area to regulate the cranial temperature.

×

The occurrence and form of sex chromosomes were investigated with the aid of C-banding and 4′-6-diamidino-2-phenylindole (DAPI) staining in 13 species of lacertid lizards. The results obtained show the presence in five species of a female heterogamety in which the two sex chromosomes have the same shape and size, but the W differs from the Z in being almost entirely heterochromatic. This condition is clearly similar to that found in some snakes and considered to be an early stage of differentiation of sex chromosomes by Singh et al. (1976, 1980). A more evolved condition may be that found in three other species in which the W is distinctly smaller than the Z. A third situation is that found in all Podarcis species which, even though they are considered to be among the more evolved species in the family, possess two sex chromosomes that are indistinguishable. In general, the situation in lacertids may be compatible with the hypothesis of sex chromosome evolution put forward by Singh et al. (1976, 1980). However a differentiation mechanism of this kind does not seem to be well established in lacertids, and is probably not the only mechanism that is in operation in this family.

×

Chromosomal inter- and intraspecific variation in Lacertidae. The karyology of various species from the family Lacertidae (Reptilia, Sauria) has been studied with conventional and C-banding techniques. The study shows that this family is not so conservative from a karyological viewpoint as considered til! now. In fact supernumerary chromosomes have been observed in two of the species investigated. Moreover an inter- and intraspecific variability has been found in the C-banding pattern of the various species studied. The situation found in Podarcis sicula is particularly remarkable. Different Cbanding patterns have been observed in three different subspecies and in two populations of the same subspecies. The C-banding technique evidences also the existence in some of the species studied of a female sex heteromorphism, in which the W chromosomes is completely heterochromatic. These observations suggest that in lacertid lizards the evolution of the sex chromosomes follows the same steps hypothesized for snakes.

×

The karyology of various species from the family Lacertidae (Reptilia, Sauria) has been studied with conventional and C-banding techniques. The study shows that this family is not so conservative from a karyological viewpoint as considered till now. In fact a higher diploid number than that generally observed in most species of Lacertidae and supernumerary chromosomes have been observed in three of the species investigated. Moreover an evident interand intraspecific variability has been found in the C-banding pattern of the various species studied. The situation found in Podarcis sicula is particularly remarkable. Different C-banding patterns have been observed in three different subspecies and in two populations of the same subspecies. These variations do not show a well defined trend and their role in the evolution of lacertid lizards is discussed. The C-banding analysis evidences also the existence in two of the species studied of a female sex heteromorphism, in which the W chromosome has the same shape and size as the Z, but differs from it in being completely heterochromatic. This situation reminds that observed in some snakes and suggests that in lacertid lizards the evolution of sex chromosomes might have followed the same steps previously hypothesized for ophidians.

×

Biologists commonly assume that parasites are locally adapted since they have shorter generation times and higher fecundity than their hosts, and therefore evolve faster in the arms race against the host`s defences. As a result, parasites should be better able to infect hosts within their local population than hosts from other allopatric populations. However, recent mathematical modelling has demonstrated that when hosts have higher migration rates than parasites, hosts may diversify their genes faster than parasites and thus parasites may become locally maladapted. This new model was tested on the Canarian endemic lizard and its blood parasite (haemogregarine genus). In this host–parasite system, hosts migrate more than parasites since lizard offspring typically disperse from their natal site soon after hatching and without any contact with their parents who are potential carriers of the intermediate vector of the blood parasite (a mite). Results of cross-infection among three lizard populations showed that parasites were better at infecting individuals from allopatric populations than individuals from their sympatric population. This suggests that, in this host–parasite system, the parasites are locally maladapted to their host.

×

Reports of dermatophytosis in reptiles are rare. This report describes the microscopical and immunohistochemical findings in a case of dermatophytosis caused by Trichophyton spp. in a 2-year-old Tenerife lizard (Gallotia galloti) with ulcerative and pustular skin lesions. Microscopically, the lesions were characterized by superficial epidermal pustules containing heterophils with numerous fungal hyphae that stained by periodic acid–Schiff and Grocott`s stain. Fungal culture was not performed, but a panel of polyclonal antibodies specific for different fungal genera was applied to tissue sections. These immunohistochemical studies demonstrated reactivity of the hyphae only with antiserum specific for Trichophyton spp.

×

Size-related selection of insular lizards by two sympatric predatory bird species (Southern Grey Shrike and Eurasian Kestrel) was studied in an arid insular environment. The endemic lizard genus Gallotia was a key resource in the diet of both predators, constituting more than 50% of the total biomass. Shrikes captured smaller lizards than kestrels during all seasons (mean snout - vent length (SVL): 7.4 ± 1.9 vs. 9.4 ± 2.1 cm respectively), presenting a sequential use of lizard sizes and avoiding potential competition. On the other hand, shrikes and kestrels showed the same seasonal variation pattern, capturing the largest lizards during their breeding periods (spring). Considering lizard availability, shrikes displayed less selective predation than kestrels in all seasons. Shrikes positively selected the medium lizard size (SVL: 5-10 cm) during the nestling period, but negatively selected the small lizard size (SVL: < 5 cm) in autumn and winter, probably due to an explosion of juvenile lizards. Lastly, kestrels appeared to be more selective, negatively choosing the small lizard size but positively selecting the largest ones all the year round (SVL: > 10 cm).

×

Proteinloci von 36 Eidechsen der Art Gallotia galloti aus Teneriffa wurden untersucht. Der Gendiversitätsindex betrug bei einer Zufallsstichprobe von 24 Proteinloci 0.087. Unter insgesamt 36 untersuchten Loci wurde eine signifikante geographische Variation nur nei Transferrinen von Tieflandeidechsen festgestellt, während eine Stiuchprobe von Gallotia aus Gebirgsregionen oberhalb der Passatwolken ausschließlich Heterozygote auswies, scheinbar eine Anpassung an drastische circadiane Änderungen der Umweltbedingungen.

×

Lacertinae is one of the three lacertid lizard subfamilies with a geographical distribution confined to the Palaearctic. Several past attempts to reconstruct its phylogeny resulted in unresolved bush-like topologies. We address the question of whether the lack of resolution is due to insufficient data or whether this lack reflects a rapid succession of speciation events. We analyzed four partial and one complete gene sequences from mitochondrial and nuclear genomes, totalling roughly 3600 bp. We included 29 species representing all 19 genera suggested in recent revision of Lacertinae [Arnold, E.N., Arribas, O., Carranza, S., 2007. Systematics of the palaearctic and oriental lizard tribe Lacertini (Squamata: Lacertidae: Lacertinae), with descriptions of eight new genera. Zootaxa 1430, 1–86]. The resulting phylogeny, first, corroborates monophyly at the genus level for the suggested genera, as well as the finding that Atlantolacerta andreanskyi, until recently part of Lacertinae, belongs to the subfamily Eremiadinae. Second, we find that increasing the sequence length and combining multiple nuclear and mitochondrial sequences did not resolve the polytomy, suggesting that the inferred topology indicates a multiple cladogenesis within a short geological period, rather than a methodical artefact. Divergence time estimates, based on previous estimates of several node ages, range from 13.9 to 14.9 million years for the radiation event, however with very broad confidence interval. To associate the radiation with a narrower geological time we consider palaeogeographic and palaeoclimatic data, assuming that the Lacertinae probably evolved in Central Europe andWAsia after the collision of Africa and Eurasia. We suggest that this radiation may date to the late Langhian (ca. 14–13.5 million years) when geological events caused abrupt changes in regional water–land distribution and climate, offering a window of distinct conditions.

×

In actual society, the lifestyle that is carried out is far from everything to which we were biologically adapted. This lifestyle negatively affects the people`s health, mainly promoting stress. The objective of stress is to promote the expression of behaviors or changes in the physiology of body organs and tissues to achieve the survival of an organism that is under threat, but currently it has been seen that it is a very frequent state in adult humans . It has been shown that, in humans, stress is associated with severe disturbances of the circadian rhythm causing sleep disorders such as insomnia. This project aims to study the activity-rest rhythm (Wake-Sleep) in animals subjected to a stressful environment. For this, a group of Wistar rats (nocturnal homeothermic mammal) and a group of lizards of the species Gallotia galloti (diurnal poikilothermic reptile), both located for the first time in a nearby recording chamber, will be used. This is intended to create a stressful predator-prey environment (both species can be one or the other). If it is confirmed that stress can make circadian rhythms disappear in the rat, and / or in the lizard, it will have been shown that these rhythms have a degree of flexibility unsuspected until now.

×

Ultraviolet (UV) vision and UV colour patches have been reported in a wide range of taxa and are increasingly appreciated as an integral part of vertebrate visual perception and communication systems. Previous studies with Lacertidae, a lizard family with diverse and complex coloration, have revealed the existence of UV-reflecting patches that may function as social signals. However, confirmation of the signalling role of UV coloration requires demonstrating that the lizards are capable of vision in the UV waveband. Here we use a multidisciplinary approach to characterize the visual sensitivity of a diverse sample of lacertid species. Spectral transmission measurements of the ocular media show that wavelengths down to 300 nm are transmitted in all the species sampled. Four retinal oil droplet types can be identified in the lacertid retina. Two types are pigmented and two are colourless. Fluorescence microscopy reveals that a type of colourless droplet is UV-transmitting and may thus be associated with UV-sensitive cones. DNA sequencing shows that lacertids have a functional SWS1 opsin, very similar at 13 critical sites to that in the presumed ancestral vertebrate (which was UV-sensitive) and other UV-sensitive lizards. Finally, males of Podarcis muralis are capable of discriminating between two views of the same stimulus that differ only in the presence/absence of UV radiance. Taken together, these results provide convergent evidence of UV vision in lacertids, very likely by means of an independent photopigment. Moreover, the presence of four oil droplet types suggests that lacertids have a four-cone colour vision system.

×

Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.

×

1. Defaunation of large-bodied frugivores could be causing severe losses of crucial ecosystem functions such as seed dispersal. The immediate ecological consequences may include alteration or even collapse of seed-mediated gene flow affecting plant population connectivity, with impacts on the regional scale distribution of genetic variation. Yet these far-reaching consequences of defaunation remain understudied. 2. Here we tested whether human-induced defaunation of the Canarian frugivorous lizards (Gallotia, Lacertidae) altered within-island population connectivity and the amount and large-scale distribution of genetic variation of Neochamaelea pulverulenta (Rutaceae), which relies exclusively on these lizards for seed dispersal. Our study system defines a lizard downsizing gradient with three contrasted ecological scenarios (islands) with relatively optimal (Gran Canaria; large-sized lizards), sub-optimal (Tenerife; medium) and collapsed seed dispersal processes (La Gomera; small). We extensively sampled individual plant genotypes from 80 populations spanning the full geographic range of the plant to examine their genetic diversity, population-genetic network topologies, and the patterns of isolation both by distance (IBD) and resistance (IBR) across these three ecological scenarios. 3. Plant genetic diversity appeared unaffected by defaunation-mediated downsizing of frugivorous lizards. However, we found a reduced overall plant population connectivity together with an increased isolation by distance within the most defaunated islands (La Gomera and, to a lesser extent, Tenerife) when compared with the scenario preserving the functionality of lizard-mediated seed dispersal (Gran Canaria). The results, with a significant effect of lizard downsizing, were robust when controlling for biotic/abiotic differences among the three islands by means of isolation by resistance models (IBR). 4. Synthesis. Our results provide valuable insights into the far-reaching consequences of the deterioration of mutualisms on plant population dynamics over very large spatial scales. Conservation of large-bodied frugivores is thus essential because their irreplaceable mutualistic dispersal services maintain an extensive movement of seeds across the landscape, crucial for maintaining the genetic cohesiveness of metapopulations and the adaptive potential of plant species across their entire geographic range.

×

The loss of largest-bodied individuals within species of frugivorous animals is one of the major consequences of defaunation. The gradual disappearance of large-bodied frugivores is expected to entail a parallel deterioration in seed dispersal functionality if the remaining smaller-sized individuals are not so effective as seed dispersers. While the multiple impacts of the extinction of large bodied species have been relatively well studied, the impact of intraspecific downsizing (i.e. the extinction of large individuals within species) on seed dispersal has rarely been evaluated. Here we experimentally assessed the impact of body-size reduction in the frugivorous lizard Gallotia galloti (Lacertidae), an endemic species of the Canary Islands, on the seed germination patterns of two fleshy-fruited plant species (Rubia fruticosa and Withania aristata). Seed germination curves and the proportions of germinated seeds were compared for both plant species after being defecated by large-sized individuals and small-sized individuals. The data show that seeds of W. aristata defecated by larger-sized lizards germinated faster and in a higher percentage than those defecated by small-sized lizards, while no differences were found for R. fruticosa seeds. Our results suggest that disappearance of the largest individuals of frugivorous species may impair recruitment of some plant species by worsening seed germination. They also warn us of a potential cryptic loss of seed dispersal functionality on defaunated ecosystems, even when frugivorous species remain abundant.

×

Population phylogeographic studies are generally based solely on mtDNA without corroboration, from an independent segregating unit (i.e., nuclear genes), that the mtDNA gene tree represents the organismal phylogeny. This paper attempts to evaluate the utility of microsatellites for this process by use of the Western Canary Island lacertid (Gallotia galloti) as a model. The geological times of island eruptions are known, and well-supported mtDNA phylogenies exist (corroborated as the organismal phylogeny rather than just a gene tree by nuclear random amplified polymorphic DNAs (RAPDs)). The allelic variation in 12 populations from four islands (representing five haplotype lineages) was investigated in five unlinked microsatellite loci. Analysis of molecular variance showed this data to be highly structured. A series of genetic distances among populations was computed based on both the variance in allele frequency (i.e., Fst related) and the variance in repeat numbers (i.e., Rst related). The genetic distances based on the former were more highly correlated with the mtDNA genetic distances than those based on the latter. All trees based on both models supported the primary division shown by mtDNA and RAPDs, which is dated at ca. 2.8 to 5.6 mybp (depending on calibration of the mtDNA clock) and which could, under the evolutionary species concept, be regarded separate species. This was achieved despite theoretical problems posed by the use of few loci, suspected bottlenecks, and large population sizes. The finer details were less consistently represented. Nevertheless, this study demonstrates that even a small number of microsatellites can be useful in corroborating the deeper divisions of a population phylogeny

×

A parasitological survey has been carried out to determine the relationships between host diet and parasite fauna. Diet, and infracommunities and component communities of two subspecies of lacertid lizards, Gallotia galloti galloti (Oudart, 1839) and G. g. palmae (Boettger et Müller, 1914) from Tenerife and La Palma islands (Canary Islands, Spain), have been analysed. High values of parasite infection parameters were found in both subspecies, which were only infected by nematodes of the family Pharyngodonidae. Plant matter was mainly consumed by both lizard subspecies and relevant amounts of mineral matter were also found in both hosts. Diet of these lacertid lizards was correlated with their parasite fauna formed by monoxenous nematodes parasitising herbivorous reptiles, as in tortoises and iguanid lizards. Abundance and richness of parasites increased with consumption of plant matter in G. g. galloti. Helminthological data support the idea of a tendency of both hosts towards herbivory, probably related to their own phylogeny linked to insularity.

×

In island environments, lizards tend to include plant materials into their diet at a higher proportion than in the mainland surroundings. They are considered as key elements for plant dynamics in many islands communities, where they consume a great amount of fruits. In the Canary Islands, it has been evidenced that Gallotia lizards are among the most important seed dispersers of fleshy-fruited plant species. However, if lizards’ effectiveness as seed dispersers changes or not throughout their ontogeny is still unknown. Hence, this study compares the “seed dispersal effectiveness” (SDE) provided by large and small-sized individuals of the common Canary lizard Gallotia galloti (Oudart 1839) to a group of plant species representative of the thermo-sclerophyllous shrubland, one of the most threatened habitats in the macaronesian islands. The results of this study show that large male lizards disperse a greater wealth of plants species than juveniles and female lizards. In addition, considering the quantity and quality of dispersal, large-sized lizards provide a higher SDE to plants than small-sized lizards. These results might have important consequences for the conservation of the thermos-sclerophyllous shrubland from Tenerife within a context of global change, where invasive alien predators, although without driving native species to extinction, can lead to their body size reduction.

×

We analyzed 621 lizard fecal pellets to assess the diet of the endemic lizard Gallotia galloti (Lacertidae) throughout one year in the thermophilous scrubland, the most threatened habitat in the Canary Islands. Indicating the importance of frugivory, 98.1% of pellets contained seeds from fleshy-fruited plant species (8,028 seeds in total), and the fruit volume reached 47.5%. The Canarian endemic plants Rhamnus crenulata and Canarina canariensis were most important in frequency of occurrence and number of seeds found in pellets, respectively. Lizards were more frugivorous during the summer (63.0% of volume), and seasonal variation was associated with temporal changes in availability of ripe fleshy fruits. We detected microspatial differences in the consumption of fruits and plant material. Significant correlations were found between plant cover of each species and their respective consumption by lizards. Lizards consumed invertebrates throughout the year; Formicidae, Hemiptera, Coleoptera, and Hymenoptera were the most frequently consumed prey (76.5% of the animal prey items). Our results indicate that G. galloti is one of the most frugivorous lacertids studied. The high number of undamaged seeds removed by these lizards also implies an important role in the seed dispersal processes of many fleshy-fruited plant species from this threatened habitat.

×

Some variants of the Golgi techniques have been used to study the possible origin and developmental sequence of astroglial cells in the lizard Gallotia galloti. the developmental sequence consists of progressive transformations of astroglial cells originating either from radial glia or from glioblasts. The so-called displaced radial glia, an intermediate cellular type between radial glia and astrocytes, indicate the radial glia/astrocytes transformation. Apparently, glioblasts also evolve into astroblasts that, in turn could develop into immature protoplasmic or fibrous astrocytes, precursors of mature protoplasmic and fibrous astrocytes, respectively. The present study confirms our previous ultrastructural and immunohistochemical studies on the same animal.

×

Spontaneous regrowth of retinal ganglion cell (RGC) axons occurs after optic nerve (ON) transection in the lizard Gallotia galloti. To gain more insight into this event we performed an immunohistochemical study on selected neuron and glial markers, which proved useful for analyzing the axonal regrowth process in different regeneration models. In the control lizards, RGCs were beta‐III tubulin‐ (Tuj1) and HuCD‐positive. The vesicular glutamate transporter‐1 (VGLUT1) preferentially stained RGCs and glial somata rather than synaptic layers. In contrast, SV2 and vesicular GABA/glycine transporter (VGAT) labeling was restricted to both plexiform layers. Strikingly, the strong expression of glutamine synthetase (GS) in both Müller glia processes and macroglial somata revealed a high glutamate metabolism along the visual system. Upregulation of Tuj1 and HuCD in the surviving RGCs was observed at all the timepoints studied (1, 3, 6, 9, and 12 months postlesion). The significant rise of Tuj1 in the optic nerve head and optic tract (OTr) by 1 and 6 months postlesion, respectively, suggests an increase of the beta‐III tubulin transport and incorporation into newly formed axons. Persistent Tuj1+ and SV2+ puncta and swellings were abnormally observed in putative degenerating/dystrophic fibers. Unexpectedly, neuron‐like cells of obscure significance were identified in the control and regenerating ON‐OTr. We conclude that: 1) the persistent upregulation of Tuj1 and HuCD favors the long‐lasting axonal regrowth process; 2) the latter succeeded despite the ectopia and dystrophy of some regrowing fibers; and 3) maintenance of the glutamate‐glutamine cycle contributes to the homeostasis and plasticity of the system.

×

We analysed the astroglia response that is concurrent with spontaneous axonal regrowth after optic nerve (ON) transection in the lizard Gallotia galloti. At different post-lesional time points (0.5, 1, 3, 6, 9 and 12 months) we used conventional electron microscopy and specific markers for astrocytes [glial fibrillary acidic protein (GFAP), vimentin (Vim), sex-determining region Y-box-9 (Sox9), paired box-2 (Pax2)¸ cluster differentiation-44 (CD44)] and for proliferating cells (PCNA). The experimental retina showed a limited glial response since the increase of gliofilaments was not significant when compared with controls, and proliferating cells were undetectable. Conversely, PCNA+ cells populated the regenerating ON, optic tract (OTr) and ventricular wall of both the hypothalamus and optic tectum (OT). Subpopulations of these PCNA+ cells were identified as GFAP+ and Vim+ reactive astrocytes and radial glia. Reactive astrocytes up-regulated Vim at 1 month post-lesion, and both Vim and GFAP at 12 months post-lesion in the ON-OTr, indicating long-term astrogliosis. They also expressed Pax2, Sox9 and CD44 in the ON, and Sox9 in the OTr. Concomitantly, persistent tissue cavities and disorganised regrowing fibre bundles reaching the OT were observed. Our ultrastructural data confirm abundant gliofilaments in reactive astrocytes joined by desmosomes. Remarkably, they also accumulated myelin debris and lipid droplets until late stages, indicating their participation in myelin removal. These data suggest that persistent mammalian-like astrogliosis in the adult lizard ON contributes to a permissive structural scaffold for long-term axonal regeneration and provides a useful model to study the molecular mechanisms involved in these beneficial neuron–glia interactions.

×

Reptiles are the only amniotic vertebrates known to be capable of spontaneous regeneration of the central nervous system (CNS). In this study, we analyzed the reactive changes of glial cells in response to a unilateral physical lesion in the cerebral cortex of the lizard Gallotia galloti, at 1, 3, 15, 30, 120, and 240 days postlesion. The glial cell markers glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), S100 protein, and tomato lectin, as well as proliferating cell nuclear antigen (PCNA) were used to evaluate glial changes occurring because of cortical lesions. A transitory and unilateral upregulation of GFAP and GS in reactive radial glial cells were observed from 15 to 120 days postlesion. In addition, reactive lectin-positive macrophage/microglia were observed from 1 to 120 days postlesion, whereas the expression of S100 protein remained unchanged throughout the examined postlesion period. The matricial zones closest to the lesion site, the sulcus lateralis (SL) and the sulcus septomedialis (SSM), showed significantly increased numbers of dividing cells at 30 days postlesion. At 240 days postlesion, the staining pattern for PCNA, GFAP, GS, and tomato lectin in the lesion site became similar to that observed in unlesioned controls. In addition, ultrastructural data of the lesioned cortex at 240 days postlesion indicated a structural repair process. We conclude that restoration of the glial framework and generation of new neurons and glial cells in the ventricular wall play a key role in the successful structural repair of the cerebral cortex of the adult lizard.

×

Sex chromosomes are believed to be stable in endotherms, but young and evolutionary unstable in most ectothermic vertebrates. Within lacertids, the widely radiated lizard group, sex chromosomes have been reported to vary in morphology and heterochroma- tinization, which may suggest turnovers during the evolution of the group. We compared the partial gene content of the Z-specific part of sex chromosomes across major lineages of lacertids and discovered a strong evolutionary stability of sex chromosomes. We can conclude that the common ancestor of lacertids, living around 70million years ago (Mya), already had the same highly differentiated sex chromosomes. Molecular data demonstrating an evolutionary conservation of sex chro- mosomes have also been documented for iguanas and caenophidian snakes. It seems that differences in the evolutionary conservation of sex chromosomes in vertebrates do not reflect the distinction between endotherms and ectotherms, but rather between amniotes and anamniotes, or generally, the differences in the life history of particular lineages.

×

A field study was performed to evaluate the effect of exposure to organophosphorus (OP) and carbamate (CB) pesticides on the lizard Gallotia galloti palmae. Butyrylcholinesterase (BChE) activity was measured in the plasma of 420 lizards collected from agricultural and reference areas on the Island of La Palma (Canary Islands, Spain) in two sampling periods. Exposure to cholinesteraseinhibiting pesticides was evaluated by a statistical criterion based on a threshold value (two standard deviations below the mean enzyme activity) calculated for the reference group, and a chemical criterion based on the in vitro reactivation of BChE activity using pyridine- 2-aldoxime methochloride (2-PAM) or after water dilution of the sample. Mean (GSD) BChE activity for lizards from agricultural areas was significantly lower (Fuencaliente site=2.00G0.98 mmol min_1 ml_1, Tazacorte site=2.88G1.08) than that for lizards from the reference areas (Los Llanos site=3.06G1.17 mmol min_1 ml_1, Tigalate site=3.96G1.62). According to the statistical criterion, the number of lizards with BChE depressed was higher at Fuencaliente (22% of males and 25.4% of females) than that sampled at Tazacorte (7.8% of males and 6.2% of females). According to the chemical criterion, Fuencaliente also yielded a higher number of individuals (112 males and 47 females) with BChE activity inhibited by both OP and CB pesticides. CBs appeared to be the pesticides most responsible for BChE inhibition because most of the samples showed reactivation of BChE activity after water treatment (63.3% from Fuencaliente and 29% from Tazacorte). We concluded that the use of reactivation techniques on plasma BChE activity is a better and more accurate method for assessing field exposure to OP/CB pesticides in this lizard species than making direct comparisons of enzyme activity levels between sampling areas.

×

Sleep-wake cycle is the most studied circadian rhythms and sleep is a particular field in which neuroscience has deepened. Nevertheless, sleep evolution at mammalian level is still unclear. The last hypothesis is based on the fact that the dream of mammals comes from the vigil of reptiles, and to conduct these investigations electrophysiological criteria are used. This methodology includes registering the electroencephalogram (EEG), which indicates the brain`s electrical activity and which is the main indicator of sleep. To deepen the principles of sleep, this study is presented with reptils Gallotia galloti. Considering that tricyclic antidepressants (ADT) produce a total reduction of REM sleep in mammals, it ADT would eliminate some phase of reptiles vigil, this state could be understood as the phylogenetic predecessor of REM sleep. This work has shown that imipramine (ADT) produced on the EEG of Gallotia galloti the suppressing of the startle response after an acoustic stimulus, a fact that brings further evidence of the homology between reptiles waking and mammals sleep.

×

Relationships among environmental patterns and population size of the smut lizard Gallotia galloti galloti Oudart, 1839 (Sauria Lacertidae) were examined in the context of longer time-scale variability on a sandy beach and adjacent environments of Southeastern Tenerife. Seasonal and yearly patterns in the population size were likewise analyzed in relation to climatic and anthropic variables. Six sampling plots (coastal, sweet tabaiba, tuff, lava, sandy lava and crater) were selected following a perpendicular transect to the sandy fringe that extends from the beach toward the volcanic interior. Pitfall trapping was conducted from 1984 to 2005, and capture–mark–recapture technique and the Jolly–Seber method were used to estimate population sizes. The highest population size estimates were shown on the sandy lava plot and the neighboring lava plot, reaching values of about 3500 individuals ha−1 during the spring. The population was active almost the whole year, with seasonal patterns of activity from March to October. Seasonal temperature and population size patterns were correlated but the ‘calima’ episodes produced some disturbance. Gallotia galloti galloti was one of the most abundant lizards of all the species studied and its population size has not remained stable over the study period, probably because of the absence of predation and competition, and because of human interference and environmental instability.

×

We have previously described the spontaneous regeneration of retinal ganglion cell axons after optic nerve (ON) transection in the adult Gallotia galloti. As neurotrophin-3 (NT-3) is involved in neuronal differentiation, survival and synaptic plasticity, we performed a comparative immunohistochemical study of NT-3 during the ontogeny and regeneration (after 0.5, 1, 3, 6, 9, and 12 months postlesion) of the lizard visual system to reveal its distribution and changes during these events. For characterization of NT-3(+) cells, we performed double labelings using the neuronal markers HuC-D, Pax6 and parvalbumin (Parv), the microglial marker tomato lectin or Lycopersicon esculentum agglutinin (LEA), and the astroglial markers vimentin (Vim) and glial fibrillary acidic protein (GFAP). Subpopulations of retinal and tectal neurons were NT-3(+) from early embryonic stages to adulthood. Nerve fibers within the retinal nerve fiber layer, both plexiform layers and the retinorecipient layers in the optic tectum (OT) were also stained. In addition, NT-3(+)/GFAP(+) and NT-3(+)/Vim(+) astrocytes were detected in the ON, chiasm and optic tract in postnatal and adult lizards. At 1 month postlesion, abundant NT-3(+)/GFAP(+) astrocytes and NT-3(-)/LEA(+) microglia/macrophages were stained in the lesioned ON, whereas NT-3 became downregulated in the experimental retina and OT. Interestingly, at 9 and 12 months postlesion, the staining in the experimental retina resembled that in control animals, whereas bundles of putative regrown fibers showed a disorganized staining pattern in the OT. Altogether, we demonstrate that NT-3 is widely distributed in the lizard visual system and its changes after ON transection might be permissive for the successful axonal regrowth.

×

The lizard Gallotia galloti shows spontaneous and slow axon regrowth through a permissive glial scar after optic nerve axotomy. Although much of the expression pattern of glial, neuronal and extracellular matrix markers have been analyzed by our group, an estimation of the cell loss in the ganglion cell layer (GCL) and the degree of visual function recovery remained unresolved. Thus, we performed a series of tests indicative of effective visual function (pupillary light reflex, accommodation, visually elicited behavior) in 18 lizards at 3, 6, 9 and 12 months post-axotomy which were then processed for immunohistochemistry for the neuronal markers SMI-31 (neurofilaments), Tuj1 (beta-III tubulin) and SV2 (synaptic vesicles) at the last timepoint. Separately, cell loss in the GCL was estimated by comparative quantitation of DAPI+ nuclei in control and 12 months experimental lizards. Additionally, 15 lizards were processed for electron microscopy to monitor relevant ultrastructural changes in the GCL, optic nerve and optic tract throughout regeneration. Hypertrophy of RGCs was persistent, morphology of the regenerated nerves varied from narrow to neuroma-like features and larger regenerated axons underwent remyelination by 9 months. The estimated cell loss in the GCL was 27% and two-third of the animals recovered the pupillary light reflex which involves the pretectum. Strikingly, visually elicited behavior involving the tectum was only restored in two specimens, presumably due to the higher complexity of this pathway. These preliminary results indicate that limited functional regeneration occurs spontaneously in the severely injured visual system of the lacertid G. galloti.

×

Die Kanareneidechsen der Gattung Gallotia gehören zu den chasrismatischten Vertretern der Lacertidae. Durch ihr Vorkommen auf den beliebten Urlaubsinseln, ihre Größe und ihr teils massenhaftes Auftreten sind sire auch bei Laien recht bekannt, während die packenden bis dramatischen Geschichten rund um die beinahe ausgestorbenen Rieseneidechsen die Fachleute elektrisieren. Im seltsamen Mißverhältnis dazu steht, dass diese kräftigen, teils farbenfrohen Echsen in der letzten Zeit in der Terraristik nur noch wenig beachtet worden sind. Zeit für eine Ehrenrettung!

×

Bizarre Felsstrukturen, exotische Pflanzen und gierige Eidechsen lassen sich in einem Wort zusammenfassen: Teneriffa. Die größte Insel der Kanaren ist geprägt vom Pico del Teide, Spaniensn höchsten Berg mit 3.718 m ü. NN. Dadurch bietet sie die verschiedensten Klimazonen auf engstem Raum – und eine Heimat für Kanareneidechsen mehrerer Taxa.

×

Die Pracht-Kanareneidechse ist eine besonders farbenfrohe Vertreterin ijhrer Gattung. Obwohl d9ie Tiere auf Teneriffa in großer Zahl vorkommen und regelrechte Wegelagerer-Qualitäten entwickeln, verhalten sie sich im Terrarium häufig sehr scheu. Aber auch hier kann die Eingewöhnung gelingen - und selbst mit der berüchtigten Aggressivität der Tiere untereinander kann man fertig werden.

×

Observation of introduced lizard species on the Canary Islands of Gran Canaria and Fuerteventura. Teira dugesii from Madeira has been observed on Gran Canaria, Gallotia stehlini, originally from Gran Canaria, on the island of Fuerteventura. Also on Fuerteventura, the evidence of Gallotia galloti eisentrauti, introduced from Tenerife, was confirmed.

×

Aim: Physiological and metabolic performance are key mediators of the functional response of species to environmental change. Few environments offer such a multi-faceted array of stressors as high-altitude habitats, which differ markedly in temperature, water availability, UV radiation and oxygen pressure compared to low-altitude habitats. Species that inhabit large altitudinal gradients are thus excellent models to study how organisms respond to environmental variation. -- Location: Tenerife island, Canary Islands archipelago (Spain). -- Taxon: Tenerife lizard [Gallotia galloti, Lacertidae). -- Methods: We integrated data on age structure, thermal and hydric regulatory behaviour and four metabolic and stress-related biomarkers for an insular lizard that inhabits an extreme altitudinal range (sea level to 3700ma.s.l.), to understand how an ectotherms` age, ecophysiology and metabolism can be affected by extreme environmental variation. -- Results: We found marked differences in metabolic stress markers associated with altitude (particularly in the abundance of carbonyl metabolites and relative telomere length), but without a linear pattern along the altitudinal dine. Contrary to expectations, longer telomeres and lower carbonyl content were detected at the highest altitude, suggesting reduced stress in these populations. Evaporative water loss differed between populations but did not follow a linear altitudinal gradient. Lizard age structure or thermal physiological performance did not markedly change across different altitudes. Mixed signals in life-history and thermal ecology across populations and altitude suggest complex responses to variable conditions across altitude in this species. -- Main Conclusions: Our integrative study of multiple functional traits demonstrated that adaptation to highly divergent environmental conditions in this lizard is potentially linked to an interplay between plasticity and local adaptation variably associated with different functional traits.

×

Whereas the range size of endangered species is undoubtfuly useful to predict risk of extinction, the role of their life-history characteristics is much less clear, and their effects may depend on the nature of the threatening factors. Such factors, for instance, are known to be different on islands and on the mainland. We used phylogenetically based statistical analyses to study the relationships among conservation status, insularity, range size, and life-history traits in a clade of Western Palaearctic lacertids including insular and continental species. These lizards are ecologically similar, but they show wide variation in life-history traits and vulnerability to extinction. Insular species of a given size had smaller clutches than mainland ones. Degree of threat was best predicted by a logistic regression including range size, insularity, clutch size, and the insularity × clutch size interaction. On the mainland, but not on islands, threatened species had smaller clutches than non-threatened ones. On islands, small clutch size is probably an adaptive trait, and it might predispose certain species to extinction, but the intrinsic characteristics of such species remain unclear. However, small clutch size was a good predictor of extinction risk on the mainland, having evolved most frequently in late maturing species from montane habitats in which climatic conditions limit their reproductive output and increase their vulnerability to stochastic hazards or habitat fragmentation.

×

The last species list of the European herpetofauna was published by Speybroeck, Beukema and Crochet (2010). In the meantime, ongoing research led to numerous taxonomic changes, including the discovery of new species-level lineages as well as reclassifications at genus level, requiring significant changes to this list. As of 2019, a new Taxonomic Committee was established as an official entity within the European Herpetological Society, Societas Europaea Herpetologica (SEH). Twelve members from nine European countries reviewed, discussed and voted on recent taxonomic research on a case-by-case basis. Accepted changes led to critical compilation of a new species list, which is hereby presented and discussed. According to our list, 301 species (95 amphibians, 15 chelonians, including six species of sea turtles, and 191 squamates) occur within our expanded geographical definition of Europe. The list includes 14 non-native species (three amphibians, one chelonian, and ten squamates).

×

The expansion of urban areas and the correspondinganthropic actions have caused species to change their morphology and behavior compared with the individuals of the same species that live in rural areas. These changes have been shown to occur in several species and are considered to be the result ofbehavioral plasticity or micro-evolutionary changes. The initialobjective of this study was to analyze if there were differences in morphology and behavior between two different populations of Gallotia galloti, living respectivelyin urban and rural areas of Tenerife. Morphological and behavioral characteristics could only be taken from individuals of a rural population (3 males and 6 females). The statistical analysis of data obtained showed significative differences between sexes in: Snout-vent length, (SVL),pileus width (PW), head height (HH), and length of the two forelimbs. However, there were non-significant differences between sexes in the selected behavioral parameters. In order to obtain a wider understanding of this subject, Ialso performed abibliographic review in lizards of several species. This revision revealed specific changes in morphological and behavioral parameters between individuals living in urbanized areas in comparison with those of natural habitats, as well as some potential explanation for them.

×

Elements of the herpetofauna are in the author`s opinion of great importance for the zoogeographical division of the Palaearctic region. It is suggested that this region be divided into the following four subregions: 1/ arctic, 2/ boreal Euro-Siberian, 3/ bo- real Himalayan-Manchurian and 4/ Mediterranean-Central-Asiatic.

×

Restriction fragment length polymorphisms of 6 base pair recognising endonucleases are used to reconstruct the phylogeny of the endemic Canary Island lacertid, Gallotia. The division into conventional species is upheld by this molecular analysis and the western Canary Island lizard (G. galloti) and eastern Canary Island lizard (G. atlantica) are hypothesized to be sister species. A more comprehensive study of the intraspecific relationships of G. galloti, based on nineteen restriction enzymes, indicates that there are distinct southern and northern lineages within this species. The phylogenetic analysis does not uphold the conventional subspecies, but suggests an alternative arrangements with one northern (La Palma, Tenerife) and one southern (Gomera, Hierro) subspecies. The inferred timing of molecular divergence of populations of G. galloti, based on RFLP analysis, is compatible with the geological timing for island origin and fossil data. Mantel tests show that mitochondrial RFLP divergence is correlated with mitochondrial 12s rRNA and cytochrome oxidase I senquence divergence and highly correlated with mitochondrial cytochrome b sequence divergence.

×

berücksichtigt sie nicht die kleinen Inselchen, die von G. galloti bewohnt werden. Auch die bei anderen Eidechsen beobachtete positive Korrelation zwischen Inselgröße und populationsinterner Variabilität existiert nicht bei Gallotia. Dagegen besteht eine sehr eine Beziehung (r ≥ 0.94) zwischen Körpergröße und Variabilität bei allen Populationen von Gallotia, die für beide Geschlechter und verschiedene Merkmalstypen bemerkenswert durchgängig ist. Die Variabilität des Phänotyps wird durch ontogenetische Homoeostase-Mechanismen in der Weise beeinflußt, daß eine starke Tendenz zur Homoeostasis nur eine geringe Variation in der phänotypischen Ausprägung der Gene erlaubt. Umgekehrt gilt infolgedessen, daß die hohe potentielle Wachstumsrate großer Eidechsen einer weniger strengen Kontrolle unterliegt. Hierdurch dürfte zu erklären sein, warum großwüchsige Eidechsenarten eine stärkere phänotypische Variabilität zeigen.

×

Even though, from Darwin onwards, interisland evolution has been a cornerstone of evolutionary theory it has not been possible to determine to what extent this geographic variation reflects the phylogeny (e.g., pattern of island colonization) or ecogenetic adaptation to different ecological conditions on each island. Using the morphology of western Canary Island lacertids (Gallotia galloti) as an example, a procedure is explored that gives a preliminary answer to this problem when there are a limited number of islands. The phylogenetic component (represented by patristic distances derived from 1005 mitochondrial DNA [mtDNA] base pairs) can be separated from two potential ecogenetic factors (environmental richness and climate) by partial Mantel tests. This reveals that, although these components interact, some characters are correlated primarily to biodiversity/paucity (e.g., size), others are correlated to wet and lush environments (e.g., dorsal pattern), and others are correlated primarily to the phylogeny (e.g., sexual leg markings). The former two correlations may be due to ecogenetic adaptation to current ecological conditions, wheras the latter reflects historical processes.

×

Microgeographic variation of the vegetarian lizard Gallotia galloti within the island of Tenerife is described using univariate analysis, correlation, multiple group principal component analysis, canonical analysis, transects, and contours. The size varies locally in a mosaic pattern while head shape shows a WNW–ESE cline in the south. The scalation (scale and femoral pore counts) has two facets to its geographic variation, both of which are incongruent with the primary variation in the size and shape. The scalation shows categorical variation (stepped cline) between northern and southern populations and also a strong clinal relationship with altitude. The possible causes of this variation are considered and adaptation to current ecological conditions appears to be implicated for at least the altitudinal variation, although the pertinent factors are not obvious. It is apparent that vertebrate populations distributed across small islands do not necessarily offer the advantage of a discrete homogeneous unit for evolutionary studies but can offer the opportunity for studying microgeographic variation.

×

The lacertid lizard (Gallotia stehlini), an endemic of Gran Canaria, shows no visually obvious geographic variation, yet all seven scalation characters that were examined exhibit significant geographic variation. The number of collar scales, scales along the ventral trunk and femoral pores are correlated with habitat type, while the number of femoral pores is correlated negatively with altitude. Mantel tests were used to compare simultaneously an observed pattern with three hypothesized patterns (habitat type, altitude and proximity). They indicate that, while several individual characters are significantly associated with the putative causal factors of habitat type and altitude, there is no association between an overall scalation distance matrix and habitat type, or altitude when the effect of proximity is removed. Consequently, one should consider the individual characters as well as the multivariate generalized distances. Some of the observed patterns of geographic variation in scalation are very similar to those of the small scincid lizard Chalcides sexlineatus on Gran Canaria and also parallel the altitudinal and latitudinal variation in the scalation of the Tenerife lacertid (Galotia galloti). The low level of congruence in patterns of geographic variation in individual characters (i.e. some vary with latitude, some with altitude and one varies with longitude) is consistent with the hypothesis that ecogenetically caused geographic variation may result in lower inter-character congruence than phylogenetically caused geographic variation.

×

Previous studies using partial regression Mantel tests of matrix correspondence on within-island geographic variation in the color pattern of the Tenerife (Canary Islands) lacertid lizard (Gallotia galloti) support natural selection for different north-south climatically determined biotopes but do not support any historical cause. However, tests on the DNA phylogeny based primarily on population data from 57 localities on Tenerife support the hypothesis that there were populations on two putative precursor islands that have come into secondary contact and introgressed after these islands were joined to form Tenerife by the eruption of the Canadas edifice. Subsequent partial Mantel tests continue to support the hypothesis that color pattern is adapted to the climatic biotopes even when this phylogenetic information is taken into account by (1) testing for color pattern adaptation separately within each lineage and (2) testing for color pattern adaptation across the entire island and simultaneously considering the molecular phylogenetic relationships as representing an alternative explanation. Selection has largely expunged any trace of the geological history from current morphological variation, and the introgression of these island populations after an estimated 0.7 million years of separation gives an insight into the relationships between allopatric divergence and reproductive isolation.

×

Within the island of Tenerife the lizard Gallotia galloti shows geographic variation in a range of features, most notably the colour pattern of breeding males. Numerous (7) specific causal hypotheses, both phylogenetic and ecogenetic, are proposed or plausible for this geographic variation and these are simultaneously tested against the observed multivariate pattern. The hypotheses based on the divergence in allopatry (e.g. the secondary contact of populations from the precursor islands of Anaga and Teno and the separation of high- and low-altitude populations by encircling cloud) are rejected. The hypothesis that the pattern is caused by topographically determined climatic differences within the island is not rejected. The climate may influence the balance between selection for signalling colouration for sexual/territorial purposes and natural selection for crypsis.

×

This study of the microgeographic variation in the colour pattern of the lizard, Gallotia galloti, within Tenerife has three facets. One, an analysis of the population distribution and density in relation to physical conditions; two, univariate and multivariate descriptions of the pattern of geographic variation; and three, formal testing of a range of causal hypotheses for these geographic patterns. The range is not divided into separate allotheses high- and low-altitude populations by a inaptitude ring of ground-level cloud although there is a drop in population-density in the middle altitudes. Multiple regression indicates that, or the factors measured, this is primarily due to a decrease in insolation. The pattern of geographic variation in the six independent colour pattern characters is portrayed by contouring the 67 locality means. There is generally good congruence among these patterns and a canonical analysis indicates that the generalized pattern of geographic variation is largely unidimensional and can therefore be represented adequately by (and portrayed by contouring) the first canonical variate. Seven causal hypotheses, from a range of possible and previously suggested causes, are considered. The procedure for testing these hypotheses should depend on their dimensionality and that of the observed pattern. Since all the observed and hypothesized patterns are basically unidimensional the seven hypothesized patterns were simultaneously tested against each observed pattern (individual characters and canonical variate) by partial correlation. All the previously suggested ‘phylogenetic’ hypotheses based on divergence in allopatry are rejected. The hypotheses that the geographic variation in the colour pattern is caused by the topographically determined climate cannot be rejected. The character state changes can be explained by a balance between sexual selection for ‘attractive’ colouration and natural selection, via predation, for cryptic colouration.

×

This study of the microgeographic variation in the colour pattern of the lizard, Gallotia galloti, within Tenerife has three facets. One, an analysis of the population distribution and density in relation to physical conditions; two, univariate and multivariate descriptions of the pattern of geographic variation; and three, formal testing of a range of causal hypotheses for these geographic patterns. The range is not divided into separate allotheses high- and low-altitude populations by a inaptitude ring of ground-level cloud although there is a drop in population-density in the middle altitudes. Multiple regression indicates that, or the factors measured, this is primarily due to a decrease in insolation. The pattern of geographic variation in the six independent colour pattern characters is portrayed by contouring the 67 locality means. There is generally good congruence among these patterns and a canonical analysis indicates that the generalized pattern of geographic variation is largely unidimensional and can therefore be represented adequately by (and portrayed by contouring) the first canonical variate. Seven causal hypotheses, from a range of possible and previously suggested causes, are considered. The procedure for testing these hypotheses should depend on their dimensionality and that of the observed pattern. Since all the observed and hypothesized patterns are basically unidimensional the seven hypothesized patterns were simultaneously tested against each observed pattern (individual characters and canonical variate) by partial correlation. All the previously suggested ‘phylogenetic’ hypotheses based on divergence in allopatry are rejected. The hypotheses that the geographic variation in the colour pattern is caused by the topographically determined climate cannot be rejected. The character state changes can be explained by a balance between sexual selection for ‘attractive’ colouration and natural selection, via predation, for cryptic colouration.

×

Although explicit rules can be used to hypothesise an inter-island colonization sequence from a molecular phylogeny, and statistical methods can be used to assist in partitioning historical factors from current selective factors, this latter process has limited efficacy where there are a limited number of islands. Studying numerous populations within small, but heterogenous, islands allows a better understanding of the factors causing geographic variation. Three main approaches have been used to study within-island geographic variation using lizards on Canarian and Lesser Antillean archipelagos: (i) matrix correspondence tests and their partial regression/correlation extensions on morphological and molecular data; (ii) identification of within island patterns of morphological geographic variation paralleled on independent islands; and (iii) large scale field experiments on selection. These studies reveal that, even on small islands, ‘island populations’ may not be homogeneous in morphology, or molecular phylogeny, and that natural selection for current ecological conditions appears to be a primary force influencing morphological population differentiation, irrespective of phylogenetic history.

×

A novel source of nuclear DNA information from random amplified polymorphisms (RAPD) and a wide‐range mitochondrial DNA information (cytochrome b, cytochrome oxidase, and 12s rRNA sequence, RFLP from 4‐base and 6‐base recognition endonucleases) are used to reconstruct the population phylogeny of the western Canary Island lizard, Gallotia galloti, which, for geological reasons, has been subject to dispersal but not vicariance. Interpretation of DNA phylogenies in terms of colonization sequence indicates that G. galloti arose in Tenerife and dispersed westward in two independent pathways: north from north Tenerife to La Palma, and south from south Tenerife to Gomera to Hierro. The direction and timing of colonization by DNA divergence is entirely compatible with geological time and sequence of island origin.

×

Die Verbreitung und Inkonsistenz einiger konventioneller diagnostischer Merkmale bei zwei rezenten Formen von Gallotia (galloti und atlantica) sind Anlaß zu einer Untersuchung, ob es sich bei diesen um eigenständige Arten handelt. Phylogenetische und multivariate Analysen einer großen Anzahl von Merkmalen der Beschuppung und von Körperproportionen zeigen, daß die Unterschiede zwischen galloti und atlantica durchgehend größer sind als zwischen Populationen beider Formen; sie sind also “gute” Arten. Es gibt einige, allerdings nicht eindeutige Hinweise darauf, daß es sich bei galloti und stehlini um Sachesternarten handelt, während atlantica mit beiden weniger nah verwandt ist.

×

Illustrated by specimens of Gallotia galloti palmae from the south and northwest of the Canary Island La Palma the noticeable colour adaptation to their habitat is documented. We assume that these colourations are the result of selective pressure.

×

areas in different landscapes and climatic zones. Our special interest was the herpetofauna of this island that is poor in species numbers but nonetheless very interesting. One focus was the search for the Tenerife Speckled Lizard (Gallotia intermedia) in the South and Southwest of the island.

×

During two holiday stays (27.9.–11.10.2016 and 05.03.–12.03.2017) on the Canary Island of La Palma we undertook some herpetological photo excursions. The high variability of the lizard Gallotia galloti palmae was particularly impressive. With the following selection of photographs, which also includes pictures from the south of La Palma made in 2005, we would like to present the interesting herpetofauna as well as the landscape of the island that is full of contrast.

×

We have studied the organization of the midbrain radial glia in embryos of Gallotia galloti using the fluorescent lipophilic dye 1,1_-dioctadecyl-3,3,3_,3_-tetramethylindocarbocyanine perchlorate (DiI) and the antibodies H5 and RC2. Our goal was to verify if the radial glia takes part in the midbrain boundaries formation and if it defines different zones. Our exam reveals two clear limits, anterior or mesencephalic–diencephalic (m/d) and posterior or mesencephalic–rhombencephalic (m/r), that can be defined as the borders where the midbrain radial glia processes end. Moreover, fasciculate radial glia processes characterize these limits totally or partially. They coincide with gene expression limits and with cytoarchitectonic limits defined by other criteria. Six different subdivisions, five alar and one basal, can be defined according to radial glia distribution, fasciculation, and immunohistochemical features. The ventral part of the alar region is defined by an RC2-positive bundle of radial glial cells. This bundle supposes a trustworthy landmark to point out the tectal/ tegmental boundary. We hypothesize that this pattern of midbrain radial glia represents a basic model in amniota.

×

In the striatum, thalamus and cerebellum of a Lacertid reptile, we have found three types of cellular death during embryonic development, both at the light and electron microscopic level. The first affects the undifferentiated neuro-epithelial cells and is commonest during the early stages (E. 32-E. 36). The second corresponds to the type of `nuclear` death described in the bibliography and reaches a maximum in the middle embryonic period (E. 37-E. 39); nevertheless important variations were observed in different zones. The third is the same as the `cytoplasmic` death type and appears in the perinatal stages. Phagocytosis involved in the elimination of dead cells is of two types. One is associated with early death and is carried out by undifferentiated neuro-epithelial cells. The other is carried out by microglial cells which appear around Stage 37. Much cellular debris was observed in the intermediate zone and this was associated with the second type of phagocytosis. In both cases lipid production was associated with the degenerative process. Comparison of the temporal cellular death pattern with synaptogenesis, gliogenesis and maturation of neuronal processes is consistent with the view that the various types of cellular death found by us had different causes.

×

The relationship between an endemic lizard (Gallotia galloti) and plants with fleshy fruits was examined in a xeric habitat on the island of Tenerife, Canary Islands. An analysis of 441 droppings collected in May 1991, showed that fruits are an important item in the diet of this omnivorous lizard; 92% and 56% of droppings contained fruits from two different areas. Fruits of seven plant species were found in the droppings: Rubia fruticosa, Neochamaelea pulverulenta, Withania aristata, Lycium intricatum, Atriplex semibaccata, Opuntia dillenii and Scilla cf. haemorrhoidalis. The number of fruit species consumed at each area by G. galloti was related to their availability. Seed Viability did not differ between control seeds and seeds from the droppings, except for N. pulverulenta and L. intricatum, where viability was higher in control seeds. The gut passage of seeds significantly reduced the germination of R. fruticosa and N. pulverulenta, increased that of W aristata while no differences were found for the rest. Gallotia galloti preferred rocky and grassy sites with,less open ground and more shrub cover >50 cm in height). This should produce a non-random seed shadow in the habitats, potentially affecting the distribution of species with fleshy fruits. Omnivorous lizards on islands can act as important seed dispersers over short distances for plant species with fleshy fruits, actively influencing both their relative abundance and vegetation structure in xeric habitats.

×

Omnivorous endemic Canarian lacertids (Gallotia atlantica and G. galloti) do not present any specific digestive and physiological adaptations to herbivorous diet, compared to species and populations with a different degree of herbivory in the Canarian archipelago. The only characteristics that could be related to the type of diet were the number of cusps per tooth (between species) and the number of small stones contained in droppings (between species and populations). The rest of measured traits were correlated with lizard size and for this reason G. galloti has longer intestines, heavier stomachs and livers, more teeth and cusps, and longer gut passage. These data suggest that body size is a major determinant of the reliance on plant food (mainly fleshy fruits) in these lizards and facilitates mutualistic interactions with fleshy-fruited plant species.

×

We analyzed the frugivorous diet of the lizard Gallotia galloti, a Canary Island endemic, in relation to season and fruit availability in a xeric habitat from Tenerife. Gallotia galloti was omnivorous throughout the year (including >59% of plant material by volume in fecal pellets); only in the winter months (December and January) did invertebrates dominate the diet (>73% in volume). The most remarkable aspect of the diet was the high level of consumption of fleshy fruits, showing pronounced seasonal variation (from 30% in January to 95% in April in frequency of occurrence). Variation in fleshy fruit consumption was associated with seasonal patterns of fruits availability. A total of 4710 seeds were found in 1120 droppings analyzed during the entire year corresponding the majority to Rubia fruticosa and Plocama pendula (Rubiaceae). The extensive consumption of fleshy fruits during seven months of the year (>50% by volume) suggests G. galloti is an important seed disperser in the Canary Islands. These results contrast with the majority of continental lacertids that are insectivorous.

×

We tested the hypothesis that an evolutionary trade-off exists between the capacity to run on level terrain and the ability to climb inclined structures in lacertid lizards. Biomechanical and physiological models of lizard locomotor performance suggest that the morphological design requirements of a ground-dwelling vs. scansorial life style are difficult to reconcile. This conflict is thought to preclude simultaneous evolution of maximal locomotor performance on level and inclined terrain. This notion has been corroborated by comparative studies on lizard species from other groups (Anolis, Chamaeleo, Sceloporus), but is not supported by our data on 13 species from the family Lacertidae. We found no indication of a negative association between maximal sprint speed of lizards over a level racetrack (indicative of ground-dwelling locomotor performance), on an inclined stony surface (indicative of climbing performance over rock faces) and inclined mesh surface (indicative of clambering performance among vegetation). Moreover, morphological characteristics associated with fast sprinting capacities (e.g. long hind limbs) apparently enhance, rather than hinder climbing and clambering performance. We conclude that in our sample of lacertid lizards, the evolution of fast sprinting capacity on level terrain has not inflicted major restrictions on climbing and clambering performance.

×

The aim of this study was to determine if divergence in habitat use among lacertid lizards is paralleled by morphological differentiation. For 35 lacertid species, we measured body, head and limb dimensions. Habitat use was inferred from the literature: ground-dwelling on open terrain, ground-dwelling in vegetated areas, shrub-climbing, tree-climbing, saxicolous (i.e. rock-climbing). Traditional (i.e. non-phylogenetic) statistical analyses suggest morphological differences among species groups with different habitat use. Ground-dwelling species from open habitats tend to have longer femurs, tibiae and humeri (relative to body length) than other groups. Cursorial (i.e. level-running) species have relatively high heads and trunks compared to climbing species. These differences follow biomechanical predictions and it is tempting to consider tham as adaptations to habitat use. However, phylogenetic analyses of the data fail to establish a clear relationship between habitat use and morphology in the data set considered. There is a weak indication that the differences in head and trunk height have evolved as an adaptation to different habitat use, but the differences in relative limb dimensions among species groups with different habitat use vanish. Either adaptation of limb dimensions to habitat use has not occurred in lacertid lizards, or our methods are unable to demonstrate such an adaptation. We show that uncertainties in the topology of the phylogenetic tree used are unlikely to influence the outcome of our study. We also address the fact that habitat use is often similar in different branches of the phylogenetic tree, and the consequences this may have for the power of our statistical analyses.

×

Microhabitat use and antipredator behaviour (i.e. behavioural response to a bird model and refuge microhabitat) was measured in an experimental set-up for 11 lacertid lizard species. Additionally, locomotor performance (sprint speed, climbing and clambering speed, manoeuvrability and endurance) of the same species was quantified. The results showed considerable interspecific variation in microhabitat use, behavioural response and choice of refuge microhabitat. Part of that variation could be linked to differences in locomotor capacity. Species that frequently made use of open microhabitats tended to be fast sprinters, but had limited endurance. The behavioural data suggest these species will not start running before the predator is close at hand, and thus having high sprint capacities might be more beneficial than great endurance. Species that spent most of their time on vertical elements appeared to be fast climbers. As such microhabitats tend to be quite exposed, lizards living there are conspicuous to predators and being able to escape fast seems relevant. Contrary to our expectations, species mostly observed in the vegetated microhabitats did not excel in clambering capacity or manoeuvrability. Possibly, dense vegetation constitutes a safe harbour and species may no longer be under selection for locomotor speed. Behavioural response when confronted with an aerial predator was context-dependent in most species: most lizards fled more when in open or vertical microhabitats than when in densely vegetated ones. Moreover, when fleeing most species sought refuge in the vegetation. These findings support our idea that vegetated patches may constitute a safe harbour for lacertids.

×

Morphological and physiological considerations suggest that sprinting ability and endurance capacity put conflicting demands on the design of an animal`s locomotor apparatus and therefore cannot be maximized simultaneously. To test this hypothesis, we correlated size-corrected maximal sprint speed and stamina of 12 species of lacertid lizards. Phylogenetically independent contrasts of sprint speed and stamina showed a significant negative relationship, giving support to the idea of an evolutionary trade-off between the two performance measures. To test the hypothesis that the trade-off is mediated by a conflict in morphological requirements, we correlated both performance traits with snout-vent length, size-corrected estimates of body mass and limb length, and relative hindlimb length (the residuals of the relationship between hind- and forelimb length). Fast-running species had hindlimbs that were long compared to their forelimbs. None of the other size or shape variables showed a significant relationship with speed or endurance. We conclude that the evolution of sprint capacity may be constrained by the need for endurance capacity and vice versa, but the design conflict underlying this trade-off has yet to be identified.

×

To understand the evolution of biological traits, information on the degree and origins of intraspecific variation is essential. Because adaptation can take place only if the trait shows heritable variation, it is important to know whether (at least) part of the trait variation is genetically based. We describe intra- and interindividual variation in three performance measures (sprint speed, climbing, and clambering speed) in juvenile Gallotia galloti lizards from three populations and examine how genetic, environmental (incubation temperature), and ontogenetic (age, size) effects interact to cause performance variation. Moreover, we test whether the three performance traits are intercorrelated phenotypically and genetically. Sprint speed is highest in juveniles incubated at the lowest temperature (26 degrees C) irrespective of population. Climbing speed differs among populations, and the differences persist at least until the lizards are 30 wk old. This suggests that the three populations experience different selective pressures. Moreover, mass, snout-vent length, and hindlimb length seem to affect climbing performance differently in the three populations. The variation in sprinting and climbing ability appears to be genetically based. Moreover, the two performance traits are intercorrelated and thus will not evolve independently from each other. Clambering speed (i.e., capacity to climb up an inclined mesh) varies among individuals, but the origin of this variation remains obscure.

×

The role of the sympathetic limb of the autonomic nervous system (ANS) in the mediation of oscillations in consecutive beat-to-beat RR interval (RRI) and systolic blood pressure (SBP) values of lizards, Gallotia galloti, was investigated using spectral analysis and measuring effects of autonomic blockers. a-Adrenergic blockade decreased the power spectral density (PSD) of both RRI and SBP very low frequency (VLF: 0.007–0.055 Hz) and low frequency (LF: 0.055– 0.150 Hz) bands, whereas b-adrenergic blockade increased the PSD of both RRI- and SBP-VLF and RRI- and SBP-LF bands. These findings suggest that in lizards 1) the VLF and LF peaks of RRI and SBP power spectra are a-adrenergic mediated, and that 2) the b-adrenergic activity of the sympathetic system may act buffering all RRI and SBP oscillations below 0.150 Hz. These results, when analyzed jointly with the ones obtained from a previous study (De Vera and González. 1997. Comp Biochem Physiol 85A:389–394) on the effects of parasympathetic blockade on lizards’ RRI and SBP oscillations, demonstrate that these reptiles, like mammals, exhibit spontaneous short-term oscillations in their HR and SBP which are mediated by the ANS. However, unlike mammals, the RRI and ABP low-frequency oscillations in Gallotia seem to be similarly affected by the ANS and appear to be powered by a-adrenergic and parasympathetic activities and buffered by b-adrenergic activity.

×

ECG and EEG signals were simultaneously recorded in lizards, Gallotia galloti, both in control conditions and under autonomic nervous system (ANS) blockade, in order to evaluate possible relationships between the ANS control of heart rate and the integrated central nervous system activity in reptiles. The ANS blockers used were prazosin, propranolol, and atropine. Time-domain summary statistics were derived from the series of consecutive R-R intervals (RRI) of the ECG to measure beat-to-beat heart rate variability (HRV), and spectral analysis techniques were applied to the EEG activity to assess its frequency content. Both prazosin and atropine did not alter the power spectral density (PSD) of the EEG low frequency (LF: 0.5–7.5 Hz) and high frequency (HF: 7.6–30 Hz) bands, whereas propranolol decreased the PSD in these bands. These findings suggest that central b-adrenergic receptor mechanisms could mediate the reptilian waking EEG activity without taking part any a1-adrenergic and/or cholinergic receptor systems. In 55% of the lizards in control conditions, and in ~43% of the lizards under prazosin and atropine, a negative correlation between the coefficient of variation of the series of RRI value (CVRRI) and the mean power frequency (MPF) of the EEG spectra was found, but not under propranolol. Consequently, the lizards’ HRV-EEG–activity relationship appears to be independent of a1-adrenergic and cholinergic receptor systems and mediated by b-adrenergic receptor mechanisms.

×

Electroencephalograms of medial cortex and electromyograms of intercostal muscles (EMG-icm) were simultaneously recorded in the lizard, Gallotia galloti, during two daily time periods (at daytime, DTP: 1200–1600 h; by night, NTP: 0000–0400 h), to investigate whether a relationship exists between the respiratory and cortical electrical activity of reptiles, and, if so, how this relationship changes during the night rest period. Testing was carried out by studying interdependence between cortical electrical and respiratory activities, by means of linear and nonlinear signal analysis techniques. Both physiological activities were evaluated through simultaneous power signals, derived from the power of the low-frequency band of the electroencephalogram (pEEG-LF), and from the power of the EMG-icm (pEMG-icm), respectively. During both DTP and NTP, there was a significant coherence between both signals in the main frequency band of pEMG-icm. During both DTP and NTP, the nonlinear index N measured significant linear asymmetric interdependence between pEEG-LF and pEMG-icm. The N value obtained between pEEG-LF vs. pEMG-icm was greater than the one between pEMG-icm vs. pEEG-LF. This means that the system that generates the pEEG-LF is more complex than the one that generates the pEMG-icm, and suggests that the temporal variability of power in the low-frequency cortical electrical activity is driven by the power of the respiratory activity.

×

Autonomic nervous system (ANS) involvement in the mediation of the synchronization between beat-to-beat RR interval variability (RRIV) and systolic blood pressure variability (SBPV) signals of the lizard Gallotia galloti (Oudart, 1839) was investigated through linear and nonlinear time series analysis methods in a pharmacological blockade context. The ANS blockers used were atropine, prazosin, and propranolol. The interdependence between the signals was quantified by means of the magnitude-squared coherence (MSC), which measures amplitude and phase linear synchronization; the phase lag index (PLI), which evaluates the phase synchronization; and the index L, which quantifies the generalized linear and nonlinear synchronization. Atropine decreased the PLI in the low-frequency (LF: 0.01–0.05 Hz) range; prazosin decreased the MSC in the medium-frequency (MF: 0.06–0.15 Hz) range; and propranolol did not alter any of the interdependence measures. It is suggested that (i) the cholinoceptor activity mediates the phase cardiovascular synchronization in the LF range; (ii) the α1-adrenoceptor activity mediates the amplitude and phase linear cardiovascular synchronization in the MF range; and (iii) the β-adrenoceptor activity plays no role in mediating any dynamics of cardiovascular synchronization in the studied frequency range. When comparing these results with those in mammals, a lesser overall autonomic involvement in the mediation of the studied cardiovascular interdependences is seen in reptiles.

×

Both nonlinear and fractal properties of beat-to-beat R-R interval variability signal (RRV) of freely moving lizards (Gallotia galloti) were studied in baseline and under autonomic nervous system blockade. Nonlinear techniques allowed us to study the complexity, chaotic behavior, nonlinearity, stationarity, and regularity over time of RRV. Scaling behavior of RRV was studied by means of fractal techniques. The autonomic nervous system blockers used were atropine, propranolol, prazosin, and yohimbine. The nature of RRV was linear in baseline and under ß-, a1- and a2-adrenoceptor blockades. Atropine changed the linear nature of RRV to nonlinear and increased its stationarity, regularity and fractality. Propranolol increased the complexity and chaotic behavior, and decreased the stationarity, regularity, and fractality of RRV. Both prazosin and yohimbine did not change any of the nonlinear and fractal properties of RRV. It is suggested that 1) the use of both nonlinear and fractal analysis is an appropriate approach for studying cardiac period variability in reptiles; 2) the cholinergic activity, which seems to make the a1-, a2- and ß-adrenergic activity interaction unnecessary, determines the linear behavior in basal RRV; 3) fractality, as well as both RRV regularity and stationarity over time, may result from the balance between cholinergic and ß-adrenergic activities opposing actions; 4) ß-adrenergic activity may buffer both the complexity and chaotic behavior of RRV, and 5) neither the a1- nor the a2-adrenergic activity seem to be involved in the mediation of either nonlinear or fractal components of RRV.

×

Multivariate nonlinear analysis methods were applied to variability time series extracted from electrocardiographic, electrocorticographic and respiratory activities of Gallotia galloti lizards, to study interdependences between cardio-cortical activity time variations, and between cardio- respiratory activity time variations. Autonomic nervous system involvement in the mediation of such interdependences was investigated through pharmacological blockade. Cardiac variability was evaluated from the R–R intervals of the electrocardiogram (RRIv). Cortical (CORTv) and respiratory (RESPv) activity time variations were evaluated from power-data signals derived from both electrocorticogram and respiratory signal segments obtained within each R–R interval, respectively. A nonlinear index N to measure interdependence between the signals, and a surrogate data test to measure the significance and nature of the interdependences were used. A nonlinear dependence of RRIv vs. CORTv and of RRIv vs. RESPv was found. Both dependences seem to be unconnected with the functioning of both α1-adrenoceptor and cholinoceptor systems, but appear to be mediated by β-adrenoceptor mechanisms. A linear dependence of CORTv vs. RRIv and of RESPv vs. RRIv was also found. Both dependences seem to be unconnected with the operation of α1 -adrenoceptor, β-adrenoceptor and cholinoceptor systems. It is suggested that both the cardiocortical and cardiorespiratory synchronizations studied seem to be mediated by β-adrenoceptor mechanisms.

×

Observation of herpetofauna in Madeira 2015–2016 -- Article report the results of herpetological survey of Portugal islands: Madeira, Porto Santo, Ilhas Desertas and Ilhas Selvagens. The original fauna is represented mainly by sea turtles (Dermochelys coriacea, Caretta caretta, Eretmochelys imbricata, Chelonia mydas, Lepidochelys kempii, Lepidochelys olivacea), one endemic lizard species Teira dugesii and the gecko Tarentola bischoffi from Ilhas Selvagens. At least four other species have been introduced into the wild and survive freely (Hemidactylus mabouia, Pelophylax perezi, Ramphotyphlops braminus, Tarentola mauritanica), several other species have been introduced unsuccessfully or are reported only from isolated seizures (Agama agama, Hyla meridonalis, Chamaeleo chamaeleon, Pantherophis guttatus, Zamenis scalaris) and the remaining species data are considered to be erroneous (Gallotia galloti,Chalcides viridanus). Several species, including those at higher risk of invasive distribution, are kept in captivity on the islands (Graptemys pseudogeographica, Trachemys scripta, Centrochelys sulcata.

×

Environmental contamination is supposed to be a reason for population declines in reptiles. Especially intensification and expansion of agriculture are leading to increased pesticide exposure risks for wildlife. In the European Union, Special Areas of Conservation (SACs) have been established for the conservation of taxa listed in Annex II of the Habitats Directive. In the SACs, agricultural land use is legal. Therefore, we conducted a risk evaluation of pesticide exposure for Annex II reptiles by calculating proportions of land use with regular pesticide applications within SACs. Using three evaluation factors (occurrence probability, physiology, life-history aspects), a species-specific risk index was created. Nearly half of the species at above-average risk by pesticide use are globally threatened with extinction (IUCN Red List of Threatened Species). About 30% of their SACs are agriculturally used and one priority subspecies of the Habitats Directive is at highest risk (Vipera ursinii rakosiensis). Also, all evaluated fresh-water and land-dwelling turtle species are at high risk. National variation in agricultural land use in the SACs was observed. Species at above-average risk are mainly distributed in the Mediterranean and Pannonian/Continental biogeographical regions of Europe. Conservation status according to the IUCN Red List of Threatened Species as well as national differences among the member states argue for the inclusion of pesticide risk assessments in site-specific management plans for SACs to avoid regional loss of reptilian biodiversity.

×

Transection or damage to the mammalian optic nerve generally results in loss of retinal ganglion cells by apoptosis. This cell death is seen less in fish or amphibians where retinal ganglion cell survival and axon regeneration leads to recovery of sight. Reptiles lie somewhere in the middle of this spectrum of nerve regeneration, and different species have been reported to have a significant variation in their retinal ganglion cell regenerative capacity. The ornate dragon lizard Ctenophoris ornatus exhibits a profound capacity for regeneration, whereas the Tenerife wall lizard Gallotia galloti has a more variable response to optic nerve damage. Some individuals regain visual activity such as the pupillomotor responses, whereas in others axons fail to regenerate sufficiently. Even in Ctenophoris, although the retinal ganglion cell axons regenerate adequately enough to synapse in the tectum, they do not make long-term topographic connections allowing recovery of complex visually motivated behaviour. The question then centres on where these intraspecies differences originate. Is it variation in the innate ability of retinal ganglion cells from different species to regenerate with functional validity? Or is it variances between different species in the substrate within which the nerves regenerate, the extracellular environment of the damaged nerve or the supporting cells surrounding the regenerating axons? Investigations of retinal ganglion cell regeneration between different species of lower vertebrates in vivo may shed light on these questions. Or perhaps more interesting are in vitro studies comparing axon regeneration of retinal ganglion cells from various species placed on differing substrates.

×

Lizards from the Canary Islands may act as pests of several cultivated plants. As a case in point, vineyard farmers often complain about the lizards’ impact on grapes. Though no specific pesticide is used for lizards, several pesticides are used in vineyards to control for insects, fungi, etc. We therefore tested whether lizards (Gallotia galloti palmae) could detect and discriminate pesticide-treated from untreated grapes. To answer this question, we performed experiments with adults of both sexes obtained from three localities in La Palma Island. Two of them were a vineyard and a banana plantation that had been treated with pesticides and the other one was in a natural (untreated) site. In the laboratory, lizards were offered simultaneously one untreated (water sprayed) and one treated (with Folithion 50 LE, diluted to 0.1%) grape placed on small plates. The behaviour of the lizards towards the fruits was filmed and subsequently quantified by means of their tongue-flick, licks or bite rates to each of the grapes. Results showed that only lizards from the natural (untreated) site clearly differentiated the two types of grapes, performing significantly more tongue-flicks, licks and bites to the untreated than to the pesticide-treated grapes. Lizards captured at the other two sites (cultivated fields with pesticide treatment), did not show a signifi-cantly different response to the two types of grapes. These results suggest that lizards living in or near cultivated fields may be habituated to pesticide-treated food and, therefore, do not clearly discriminate treated from untreated food items. However, another possibility is that natural selec-tion (or maybe resistance) could be responsible by these individuals in the populations showing this kind of pesticide insensitiveness.

×

The development of radial glia and astrocytes in the telencephalon of the lizard Gallotia galloti was studied by immunohistochemistry with anti-vimentin and anti-GFAP antibodies. Vimentin appears at embryonic stage 32 (E32) in the proliferative zone of the lateral ventricle and subpial end-feet in the marginal zone. At E34-35 the staining intensity for vimentin in all radial glia is maximal. It then decreases and disappears in most structures in adult animals. GFAP appears at E35 in the end-feet in the marginal zone and its intensity increases until adult hood, particularly in radial and sinuous fibers and in fibers that originate from the sulci and invade the ventral striatum and the septum. In contrast, the reaction is weak in the cortex, in the anterior dorso-ventricular ridge, and in the amygdala nuclei. Radial glia is still present in the adult, and the composition of its intermediate filaments changes during development from vimentin to GFAP. No GFA-positive cell bodies except those of ependymal glia were detected in telencephalon.

×

A study was made of the maturation of glial precursors in the subpallial nuclei during the development of the central nervous system of the lizard Gallotia galloti. At the ultrastructural level these cells resemble developing glial cells previously described in mammals. Early glioblasts, light and dark glioblasts, astroblasts, oligodendroblasts, and active oligodendrocytes predominate during the prenatal period. Immature and satellite astrocytes as well as light and medium oligodendrocytes are the main cells observed between hatching and the early postnatal period. The early postnatal period is characterized by the presence of medium and satellite oligodendrocytes, most of which become dark oligodendrocytes in the adult. The thickness of myelin sheaths increases between hatching and adult age. Gliofilament-rich mature astrocytes similar to those seen in the midbrain of these animals were never found, not even in adults. The paucity of gliofilaments in immature astrocytes explains why we could not detect perikarya containing glial fibrillary acidic protein in the telencephalon of Gallotia galloti (Yanes et al., [1990] J. Comp. Neurol. 295:559–568). The presence of glioblasts and immature astrocytes in the subpallial nuclei of lizards suggests that these animals could serve as particularly valuable models in studies of glial regeneration in the central nervous system.

×

The ventral striatum nucleus (VS) begins development at Stage 31 (E. 31) from the neuroblasts which proceed from the cellular proliferation of both the ventral and terminal sulci. The ultrastructural features of the neuroblasts of VS between E. 31 and E. 34 have the aspect of immature cells, but as from E. 38 neuronal maturity is gradual until hatching. At E. 34 cellular death occurs. The first degenerated cells belong to Type I (nuclear degeneration) of the pycnotic cells; as from E. 40 cytoplasmic degeneration appears. Vascularisation starts at E. 35 and from E. 38 the first synaptic contacts are observed, especially those of the axodendritic type.

×

Während einer Reise im Dezember 2013 nach Fuerteventura wurde die dortige Herpetofauna untersucht. Neben der nahezu allgegenwärtigen Atlantischen Eidechse, die hier in der Unterart Gallotia atlantica mahoratae vorkommt, und dem Kanarischen Mauergecko (Tarentola angustimentalis) wurde auf der südlichen Halbinsel Jandia auch eine eingeschleppte Population der aus dem Norden Teneriffas stammenden Gallotia galloti eisentrauti nachgewiesen. Dagegen gelang es nicht, den versteckt lebenden und nur in einigen Gebieten der Insel vorkommenden Purpurarienskink (Chalcides simonyi) aufzuspüren.

×

Während einer Reise Anfang Juni 2011 nach Teneriffa, der größten der Kanarischen Inseln, ergaben sich viele Gelegenheiten, die allgegenwärtige Westkanaren-Eidechse zu beobachten. Die Nominatform Gallotia galloti galloti bewohnt das Zentrum sowie den Süden Teneriffas, während Gallotia galloti eisentrauti im Norden und Nordosten der Insel anzutreffen ist.

×

Report on an cryptic male Gallotia galloti eisentrauti that showed the typical coloration of a female when it lived together with another male in a terrarium. After this lizard was separated and kept in another terrarium it began to change its colours to the typical male coloration wihtin a period of three weeks.