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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.

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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.

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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.

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The lizards of the genus Gallotia, which are endemic to the Canary Islands, are studied for their endo- and ectoparasites. The island-dwelling omnivorous lizards harbor protozoan parasites of the genus Sarcocystis which reveal an unusual cannibalistic mode of transmission. Haemogregarine blood parasites of as yet undetermined taxonomic status have recently been found in three Gallotia-species. An undescribed bloodsucking mite of the genus Ophionyssus, which was found on G. galloti from Tenerife, is suspected to be involved in the life cycle on the protozoan blood parasites. Further investigations on the presented parasites concerning their taxonomy, morphology, biology, and ecology are necessary.

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From the second author´s data it has arisen that Corvus corax tingitanus –a local raven- has an assorted diet, consuming fruits (and seeds) of Opuntia ficus-barbarica, Chamaecytisus proliferus, Rubia fruticosa, Phoenix canariensis and Plocama pendula. The closest populations of the two latter species live in lower biotopes, warmer than the sampled site which is probably unsuitable for the dispersed plants, despite the fact that the seeds are variable. Gallotia stehlini, an omnivorous lizard, has small territories and therefore eats just local fruits and/or seeds of Rubia fruticosa and Teline rosmarinifolia. Erinaceus algirus, a primarily insectivorous hedgehog, appears to roam to far populations of Plocama. The seed rain does not seem to be a restriction but the establishment of the plants, frequently blocked by the strong environmental contrasts among very close habitats.

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Gallotia atlantica the endemic lacertid of the eastern Canary Islands Lanzarote and Fuerteventura, has been recorded on the island of Gran Canaria for the first time. From a consideration of the peculiar distribution of the reptile on the latter island together with its interactions with the much larger G. stehlini, the local endemic species, a new hypothesis is proposed to account for the disappearance of the giant lizards of the Canaries. This hypothesis is based on a phenomenum of competitive displacement between species of differing size in which the smaller benefits.

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The systematic position of Lacerta simonyi stehlini is shordy reviewed. Same obser- vations concerning nutrition and behaviour, also mating behaviour, are described. Two clusters containing seven and eleven eggs were produced. Eight juveniles hatched from the second duster. Their morphology, growth and behaviour during the first four months are described.

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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.

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

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Our former paper (BÖHME & BINGS 1975) on the status of Lacerta s. simonyi and the paper by KLEMMER (1976) on the Canarian herpetofauna make the following addi- tional points necessary: 1. The current existence of L. s. simonyi can be documented for the first time by a photograph of a living specimen. 2. This extremely endangered lizard has been protected by the Spanish Natural Protection .Institution (ICONA), and will be listed in the Red Data Book by the IUCN. 3. Specimens from the Salmor rocks and from Hierro are identical in colour pattern and markings. .4. The temporal scalation has been shown to be variable, thus it is useless for distinguishing L. s. simonyi and stehlini. 5. As in the other Canarian lacertids stehlini also shows a tendency towards melanism. 6. L. s. stehlini reaches a maximum total length of 800 mm, whereas L. s. simonyi grows remarkably larger. Male specimens from up to one meter can occur.

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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.

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Diet and helminth fauna were analysed in Gallotia stehlini (Schenkel, 1901), a giant lacertid lizard endemic to Gran Canaria (Canary Islands, Spain) in order to explore eventual relationships between both traits. This species is mainly herbivorous, eating a large proportion of plant matter (occurrence 97.1%) including not only seeds but also leaves and other vegetative parts. Helminth fauna included many helminth species typical of herbivorous reptiles, and intestinal helminth diversity was high. A comparison with other lacertids suggests that both traits, diet and helminth fauna, result from an adaptation to insular conditions. Canarian Gallotia, a separate lineage evolving for a long time in insularity, constitutes the most modified lacertid group in this sense.

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We discuss three aspects of the thermal biology of lacertid lizards. First, we provide an overview of the available data on field body temperatures (Tb), the thermal sensitivity of various performance functions and selected body temperatures in different species of lacertid lizards. We also briefly summarise information on the mechanisms of thermoregulation. Second, we discuss recent developments to estimate the »precision« of thermoregulation, and the contribution of distinct behavioural mechanisms. Finally, we revise available evidence for the existence of evolutionary adjustments of thermal characteristics in lacertid lizards. Existing studies have mainly dealt with within- and among-species differences in thermoregulatory behaviour (selected temperatures) and thermal physiology of adults (optimal temperatures, heating rates). Available data provide only limited evidence for clear-cut evolutionary shifts in thermal physiology characteristics along climatic gradients.

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We studied the thermal sensitivity of sprint speed in the captive population of the endangered lizard Gallotia simonyi (Lacertidae) on El Hierro island and in G. stehlini, an abundant, large-sized lizard from the nearby island of Gran Canaria (Canary Islands, Spain). Among adults, lizards of both species were faster than adults of other lacertids. The sprint performance curves for both species had a flat upper plateau, and the obtained values for performance breadth were high, indicating that species attained near maximum sprint speeds over a wide range of body temperatures. Gallotia stehlini was significantly faster than G. simonyi both in absolute (cm/s) and relative speed (SVL/s). Juveniles of G. simonyi were significantly slower than juveniles of G. stehlini only in absolute speed. The lower sprint speed of G. simonyi is consistent with the hypothesis that higher vulnerability of this species to introduced predators may have played a role in its near extinction. Juveniles rather than adults from the captive population of G. simonyi should be used for reintroduction to establish wild populations, because the sprint performance of adults may have been compromised by prolonged captivity.

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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.

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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.

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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.

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The endemic reptiles on Gran Canaria, and how the Canary Islands remained colonized by the herpetofauna -- A portrait of the endemic reptile species of Gran Canaria is presented with notes on observations done by the author in December 2001. Tarentola b. boettgeri and Chalcides sexlineatus were found singularly under stones of the same rocky locations. Gallotia stehIini was observed in the vegetation of the sand dunes at Maspalomas. These species were not observed in or close to the hotels. The author suggests that the frequent spraying of pesticides against cockroaches in hotels may be the cause of its absence there. Furthermore, evidence of the colonisation sequence of the three Canary Island reptile genera is summarised.

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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.

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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.

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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.

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A karyological analysis on lizards of the Canary Islands Gallotia simonyi and G. atlantica ssp., resulted inboth cases ina formula of 2n = 40 (38.1 + 2 m; NF = 40); what, besides the results in Gallotia galloti, defines the genus Gallotia (Lacertidae) endemic of the Canary Islands as a monophyetic unit. Considering the ancestral characteristic demonstrated in several species of this genus by different authors such ads some morphological aspects (the hemipenis) as well as ethological aspects (copulatory ritual), it pointed out the important coincidence of the karyotype of these species and its relictual character. The similarities with Lacerta jayakari of Oman, are commended taking into consideration the botanical connections between the Canary Islands and south-eastern Arabia.

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De manera natural las invasiones biológicas son un fenómeno común resultante de eventos geotectónicos, climáticos u otros eventos naturales (Lodge, 1993; Arslan, 2019). Sin embargo, como consecuencia de la globalización las invasiones biológicas ocurren con mayor frecuencia, facilitando la propagación accidental de especies exóticas y el establecimiento como invasoras (Kolar & Lodge, 2001). Los orígenes de estas nuevas invasiones son diversos: comercio de especies exóticas, transporte activo (liberación deliberada) y transporte pasivo (escape de animales domésticos, transferencia de parásitos y patógenos, y polizones) (Goh & O`Riordan, 2007; Westphal et al. 2008; Hulme, 2015; Pupins et al. 2023). Para prevenir y hacer frente a las invasiones biológicas en un clima cambiante, se necesitan conocimientos sobre la biología de la invasión, los procesos y rasgos que promueven la invasión, y las posibles respuestas de las especies exóticas a las nuevas condiciones ambientales (Courchamp et al. 2017). Los contenedores de mercancías internacionales son utilizados para el transporte de material de diversos orígenes y usos (alimentación, construcción, jardinería, etc.) a través de cargueros marítimos, tren y avión, siendo la segunda causa del establecimiento de especies invasoras (Bomford et al. 2008). Existen datos de transporte accidental de serpientes y lacértidos vivos entre la Europa continental e islas adyacentes (Carretero et al. 2014; SilvaRocha et al. 2014; Ortega et al. 2016), pero es menos habitual en especies tropicales, debido a la lejanía o el tiempo en el contenedor. En España en los últimos años destacan la captura: de la víbora Porthidium lansbergii originaria de Colombia (Martínez- Silvestre et al. 2020), de la rana Hyperolius concolor originaria de Costa de Marfil (Martínez- Silvestre et al. 2019) o la Agama lebretoni originaria de Guinea Ecuatorial (Sancho & Pauwels, 2015). A estas observaciones el presente equipo, ha recopilado seis transportes accidentales más entre 2019 y 2022: cinco en Barcelona, dos introducciones de Gallotia stehlini en contenedores de fruta originarios de Gran Canaria, la introducción de Agama agama en un contenedor de madera originario de Camerun, una introducción de Agama picticauda en un contenedor de cacao originario de Guinea Equatorial, y la introducción de Psammophilus dorsalis en un contenedor de BIGBAGS originario de la India; y una en Tarragona, una introducción de Gallotia stehlini capturada en un polígono industrial. Sesión: Invasiones Biológicas

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Gallotia stehlini (Schenkel, 1901), the Gran Canaria Giant lizard This is a large lizard species of the Lacertidae family from Gran Canaria. They can reach a total length of 80 or even 90 cm. They are endemic to Gran Canaria, although there are a few introduced populations on Fuerteventura. The genus Gallotia is endemic to the Canary Islands. Several species are large, although there used to be several even larger species (up to 1,50 meter), but these are extinct now due to predation by humans and domestic animals in historical times. Gallotia stehlini is not endangered at this moment, it is a very adaptable species. Consequently, their husbandry is not difficult and they are easy to breed. The adults feed for a large part on a vegetarian diet like fruit and vegetables, although they still need some food like insects, snails and baby-mice. The juveniles feed mostly on insects and other invertebrates, although some fruit and vegetables is accepted too. For the rest their husbandry is comparable with that of other Lacertidae, although they are less aggressive towards each other.

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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.

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Ancient mitochondrial DNA sequences (378 base pairs of cytochrome b and 368 of 12S rRNA) extracted from a mum- mified extinct giant lizard, Gallotia goliath, from eastern Tenerife, Canary Islands, were used to assess the species status and relationship of this form within the genus. G. goliath is clearly a member of the G. simonyi group of the western Canary islands (Tenerife, La Gomera, El Hierro and La Palma) and is not closely related to the giant G. stehlini of Gran Canaria. Contrary to recent opinion, it is phylogenetically distinct, within the G. simonyi group, from the extant G. simonyi of El Hierro and also from the recently discovered live G. gomerana on La Gomera and from G. intermedia in north-western Tenerife. It may be the sister taxon of either all the other members of the G. simonyi group or of G. intermedia. The phylogenetic distinctness of G. goliath makes Tenerife unique among oce- anic islands in having had one giant and two medium-sized lizard species that were probably substantially herbiv- orous, the others being G. intermedia and G. galloti. Gallotia shows great community differences on other islands in the Canaries, two having a single small species, one a single giant, and three a giant and a medium-sized form.

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Während die nur fossil bekannte Lacerta (Gallotia?) goliath Mertens, 1942, bis 1,50 m Gesamtlänge erreichen konnte, werden die größten heute lebenden Kanareneidechsen Gallotia stehlini (Schnkel, 1901), 80 cm lang. Die von der Ausrottung bedrohte Hierro-Rieseneidechse, Gallotia aff. simonyi, erreicht nur etwa 50 cm. Die topotypische Population von Gallotia simonyi (Steindachner, 1889) verschwand in diesem Jahrhundert von dem von ihr bewohnten Felseiland, ebenso wie ein fossiler Verwandter von einer anderen Insel. Die von früheren Autoren geäußerten Überlegungen und Vorstellungen über das Aussterben bzw. den Rückgang dieser Gruppe von Großlacerten werden kommentiert. Es wird postuliert, daß zur Verringerung zwischenartlicher Konkurrenz die Großeidechsen eine von den sympatrischen kleineren Arten verschiedene Populationsstruktur entwickelten, charakterisiert durch eine Anhäufung von Individuen der oberen Größenklassen (durch schnelles Wachstum). Die Konzentration von Genen in größeren Individuen bedeutet eine erhöhte Gefahr der Population durch Räuber, da die großen Eidechsen einen höheren „Beuteappetenz-Index“ (Indice de Apetencia sensu José Valverde, 1967) haben ala kleinere Exemplare. Im Gegensatz zu Populationen mit einem ausgewogenen Größenklassen-Verhältnis, wo es nur einen kleinen Prozentsatz großer Individuen gibt, kann Prädation auf die Populationen der Rieseneidechsen verheerende Auswirkungen haben. Die Einbürgerung von (für diese Insellebensräume zu großen) Raubtieren, wie Hunden und Katzen, durch den Menschen, und die gleichfalls gegebene Möglichkeit der Ausbeutung der Großeidechsen-Populationen zur Ernährung der Ureinwohner werden diskutiert, wobei einige zusätzliche historische Argumente die hier vorgestellte Hypothese stützen. Biologische Interaktionen mit vom Menschen eingebürgerten Räubern sind der ursächliche Faktor für den Rückgang der großen Kanareneidechsen.

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Gallotia stehlini is an endemic lizard of Lacertidae from Gran Canaria in the Canary Islands. This lizard is omnivorous with a large range of food. As omnivorous lizards, it is commonly admitted that G. stehlini is more herbivorous than carnivorous, with very few data about active hunting on other animals than lizards and arthropods. Here we share what we think is the first record of active hunting on an adult rodent (Mus musculus) by Gallotia stehlini in the wild.

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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.

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We studied the occurrence of threat display as a defensive behavior at different temperatures in two large-sized (Gallotia simonyi and Gallotia stehlini) and two small-sized (Gallotia atlantica and Gallotia caesaris) lacertids from the Canary Islands. Lizards were chased on a linear track at five temperatures (24, 28, 32, 36, and 40 C). Only adult individuals of the two large-sized species sporadically adopted the threat display, and G. stehlini used the display more often than did G. simonyi. Among these, there was no clear pattern of relationship between temperature and probability of display nor differences between sexes.

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The cells-of-origin and the mode and site of termination of the interhemispheric connections passing through the anterior and posterior pallid commissures in the telencephalon of two lizards (Podarcis hispanica and Gallotia stehlinii) were investigated by studying the anterograde and retrograde transport of unilaterally injected horseradish peroxidase. The commissural projections arise mainly from pyramidal cells in the medial, dorsomedial, and dorsal cortices (medial subfield). Additionally some non-pyramidal neurons in the medial and dorsal cortices contribute to the commissural system. Medial cortex neurons project to the contralateral anterior septum through the anterior pallial commissure. The dorsomedial cortex projects contralaterally via the anterior pallid commissure to the dorsolateral septum and to the medial, dorsomedial, and dorsal cortices. The projection to the medial cortex terminates in two bands at the inner and outer border, respectively, of the cell layer; the projection to the dorsomedial and dorsal cortex ends in a zone in layer 1 which previously has been described to be Timm-negative, and in a diffuse band in the inner half of layer 3. The medial subfield of the dorsal cortex projects through the anterior pallial commissure to the dorsomedial and dorsal cortices with a similar pattern of termination to that found for the dorsomedial cortex. The posterior pallial commissure contains only the projections from the ventral cortex to ist contralateral counterpart and to the ventral part of the caudal medial cortex. The similarities found between this commissural system and the mammalian hippocampal interhemispheric connections are discussed.

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The dentition of Gallotia stehlini from one extant and two subfossil populations dated as 4000 and 2000 years before present was studied. Body measurements were similar in the two subfossil populations, but much greater than the largest sizes observed today in G. stehlini. The morphology of the dental cusps in this G. stehlini differs greatly from that of other Lacertidae, including other congeneric Canarian species; this has been connected with a vegetarian diet. A decrease in heterodonty with size of the animal is also seen which contrasts strongly with the models observed in the Mediterranean lacertid lizards.

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The transmission of Sarcocystis species via cannibalism seems to be common among lizards of the genus Gallotia that are endemic to the Canary Islands. Gran Canarian giant lizards, Gallotia stehlini, were screened for the presence of sarcosporidian parasites. Sarcocysts, measuring 90-400 µm in length and 60-160 µm in width, were found in the musculature of the lizards` tails. In their feces the lizards passed sporocysts of 8.5(8.2-9.4) x 6.5(5.9-7.0) µm. A series of laboratory infections was carried out to shed light on the life cycle of Sarcocystis stehlinii n. sp., proving it to be another dihomoxenous Sarcocystis species.

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The albumins from 41 species of the family Lacertidae representing a substantial part of genera as well as infrageneric groups of the collective genus Lacerta s.l. were investigated by means of the MCF technique. The data allow a chronological estimation of the most important radiation events and their correlation with paleogeographical facts. Our results are in remarkable contradiction to the phylogeny presented by ARNOLD (1989a) based mainly on morphological characters. The most important phylogenetic relationships are: 1. The genera Gallona and Psammodromus are already isolated from the other taxa since the Oligocene. We assess these main branches as subfamilies Gallotiinae and Lacertinae. 2. Lacerta s.str. and Lacerta subgenus Zootoca form the sister group of the remaining Lacertinae. 3. A colonization of Africa in the Lower Miocene has led to a separation in two lines, with mainly Eurasian and African members respectively. 4. ARNOLD`S (I.e.) `Ethiopian and advanced Saharo-Eurasian clade` proved to be a paraphyletic unit, one group of genera being more closely related to European taxa. All techniques applied to the systematics of Lacertidae hitherto are critically discussed. An area-time- hypothesis concerning the phylogeny of Lacertidae is presented. Key words: Lacertidae, phylogeny of; Gallotiinae subfam. nov.; Lacertinae subfam. nov.; micro complement fixation; albumin evolution.

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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.

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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.

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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.

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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.

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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.

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Tras 12 años de invasión de la culebra de herradura (Hemorrhois hippocrepis) en la isla de Ibiza (Baleares), debido a su transporte en grandes olivos destinados a jardinería, en 2015 aparecieron dos ejemplares de esta especie en el norte de la isla de Gran Canaria, en las inmediaciones de un vivero en el barranco de Casa Ayala, límite entre los municipios de Las Palmas de Gran Canaria y Arucas. Aunque se trata de dos casos aislados, la introducción de esta especie podría tener consecuencias nefastas para su biodiversidad, que ya está amenazada por la invasión de la culebra real de California (Lampropeltis californiae).

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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.

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Different kinds of interactions between lizards and plants in the Mediterranean basin have been described. Lizards have shown to `use` plants as a refuge against predators, as a foraging site, as a thermal microhabitat or as a food resource. In the last case, they can either act as herbivores (+/- interaction, consuming vegetative and/or reproductive parts, and damaging the plant to a higher or lower degree) or as mutualists (+/+ interaction, by behaving as legitimate pollinators and/or seed dispersers). The importance of plants as a food resource for Mediterranean lizards has been found to be high in insular habitats, espescially in small islands, where the paucity of arthropod prey availability redirects the foraging activity of lizards towards other nutrient resources. In such small islands, plants may play a major role in the trophic ecology of lacertid lizards, as suggested by recent studies. Likewise, lizards may be important both as efficient pollen transporters and seed dispersersfor a variety of plants. Some of these lizard-plant interactions are unique. The effect lizards have on the reproductive and dispersal succes of some species may be very relevant for plant preserveation, and in turn, the preserveation of prticular behavioral and ecological traits of the particular lizard populations depends, at least partly, on the plants they interact with.

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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.

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The retinotectal projection of reptiles is largely crossed. The intertectal commissure is an important pathway that interconnects directly the two sides of the optic tectum. The rostrocaudal topography of intertectal commissural fibers at the dorsal midplane was examined by means of the in vitro horseradish peroxidase (HRP) labelling technique in the lizard Gallotia stehlini. Unilateral large deposits of tracer in the optic tectum as well as smaller deposits restricted to one quadrant were used to map the intertectal fibers anterogradely. Most commissural axons reached the contralateral side grouped into a dense bundle at the transition between two structurally distinct parts of the midbrain dorsal midline. The smaller rostral zone relates laterally to the griseum tectale, whereas the larger caudal zone relates to the tectum. The intertectal fibers seem to converge on the rostralmost part of the latter midline region, even though they originate throughout the optic tectum. A rough rostrocaudal tectotopic order was detected at the midline. Retrogradely labelled neurons were best obtained by depositing HRP directly within the compact commissure at the midline. These belong to pyriform cells in the periventricular layers 3 and 5. Axons labelled from the tectum did not enter the posterior commissure nor the intervening commissural region related to the griseum tectale.

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Invasive snakes represent a serious threat to island biodiversity, being responsible for far-reaching impacts that are noticeably understudied, particularly regarding native reptiles. We analysed the impact of the invasive California kingsnake, Lampropeltis californiae—recently introduced in the Canary Islands—on the abundance of all endemic herpetofauna of the island of Gran Canaria. We quantified the density in invaded and uninvaded sites for the Gran Canaria giant lizard, Gallotia stehlini, the Gran Canaria skink, Chalcides sexlineatus, and Boettger’s wall gecko, Tarentola boettgeri. We used spatially explicit capture-recapture and distance-sampling methods for G. stehlini and active searches under rocks for the abundance of the other two reptiles. The abundance of all species was lower in invaded sites, with a reduction in the number of individuals greater than 90% for G. stehlini, greater than 80% for C. sexlineatus and greater than 50% for T. boettgeri in invaded sites. Our results illustrate the severe impact of L. californiae on the endemic herpetofauna of Gran Canaria and highlight the need for strengthened measures to manage this invasion. We also provide further evidence of the negative consequences of invasive snakes on island reptiles and emphasize the need for further research on this matter on islands worldwide.

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Lizards of the genus Gallotia, endemic to the Canary Islands, show morphological and colouration varieties that are related to within island variation in orographic and climatic characteristics. This study examines sexual size dimorphism (SSD) within and between population variation in morphological traits, and scaling relationships in G. sthelini from a southwestern locality (Tasartico) and from another (Gáldar) in the northwest of Gran Canaria. Both sites differ in climate and vegetation traits, and we hypothesised that SSD should be manifested by males having relatively larger body traits than females and that hind limb lengths should be relatively larger in individuals from the more open habitat. Results showed that one-third of the largest lizards from both populations did not differ significantly either in snout-to-vent length (SVL) nor in trunk length (TRL), but overall males had significantly larger SVL and TRL than females. Multivariate analysis showed that head width (HW) and hind limb length (HLL) were significantly larger in individuals from Tasartico than in those of Gáldar. Hind limb length was the trait that contributed most to differentiate between populations and head parameters between males and females. In both populations head and body traits scaled to TRL, head width (HW) and head depth (HD) of males having a positive allometry, and fore limb length (FLL) and hind limb length (HLL) a negative one. In relation to head length (HL), females had significantly larger TRL and smaller head depths than males; lizards from Gáldar had significantly larger trunk length (TRL), but smaller HW and HLL than those of Tasartico. We outline the multiple factors that could affect the evolution of morphometric traits of each sex, taking into account the ecological features of the two zones.

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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!

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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.

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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.

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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).

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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.

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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.

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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.

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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.

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RedEXOS is the Early Warning Network of the Canary Islands for the detection and intervention of invasive alien species. It is integrated into the State Warning Network by the Decree 117/2020, of November 19, and its main objective is to prevent the establishment of new outbreaks or populations of Invasive Alien Species (IAS) or those with invasive potential in the Canary Islands. The Network is also in charge of compiling and coordinating the information on the appearance of IAS included in the Spanish Catalog of Invasive Alien Species or in the List of worrisome invasive alien species for the outermost region of the Canary Islands, or species with invasive potential in the Canary Islands that can be identified as such by the Autonomous Community of the Canary Islands. Biological invasions are one of the main causes of biodiversity loss on islands, so early detection is very important both to achieve greater success in eradication, and to reduce costs, the complexity of the intervention and the impacts on biodiversity. This oral presentation presents two species of invasive reptiles which are included in the List of worrying invasive alien species for the outermost region of the Canary Islands in which this official network of the Government of the Canary Islands, RedEXOS, is currently involved. RedEXOS has been working, since 2017, on the early detection of invasive species or potentially invasive before they become an ecological problem in the archipelago. For this, it has a platform, which includes a mobile app and a website, developed to encourage citizen participation and to unify information on the appearance and management of IAS in the Canarian territory. The poster presented includes the balance of sightings and interventions recorded on the RedEXOS platform. Although flora requires a greater number of interventions, is the fauna the one that needs urgent interventions. Among the interventions with invasive reptiles, data of two species that are included in the List of worrisome invasive alien species for the outermost region of the Canary Islands are presented. They are Anolis carolinensis, on the island of Tenerife, and Chamaeleo calyptratus on Gran Canaria. This official network of the Government of the Canary Islands is currently working on them, doing monitoring and control tasks. Furthermore, the problem of translocated native species is presented. An example is explained with the populations of the giant lizard of Gran Canaria (Gallotia stehlini) located on other islands of the Canary archipelago.

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Pharyngodonid nematodes (Oxyuroidea) belonging to the genus Alaeuris Thapar, 1925, were collected from the posterior gut of Gallotia stehlini (Lacertidae) from Grand Canary Island. Two species Alaeuris stehlini n. sp. and Alaeuris numidica canariensis n. ssp. were identified. The new species is described in which the long thin males are characterized by narrow caudal alae, a rounded first pair of adanal papillae non pedunculate, the second pair attached and elongate, the three pair teated; a short narrow V plate and a relatively long caudal appendage. The females are also long and thin with a slightly salient vulva, a conical pointed caudal appendage, oesophageal length approximately one third of body, excretory pore below the oesophageal bulb. The new subspecies most closely resembles Alaeuris numidica numidica. (Seurat, 1918) Petter, 1966 and Alaeuris numidica madagascariensis Petter, 1966.