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Cytogenetic analysis and the patterns of alloenzyme migration were used to analyse the possible endogamic depression caused by the scarce number of specimens of the lizard still in existence. The karyotype of Gallotia simonyi has a chromosome pattern of 2N = 40 (38 accrocentric and 2 microchromosomes with a pair of NOR located in telomeric position at pair 19). There would appear to be no chromosomic definition for sex nor do variations appear in the layout of C bands over the various individuals. Protein electrophoresis has shown that all individuals are monomorphous over the 32 loci analysed. This fact reveals absence of heterocygosity and polymorphism. From the results, we discuss the possibility of total loss of genetic diversity and the application of other techniques towards confirming this extreme (analysis of mini- and macro-satellites). An optimisation of the present cross breeding system used for the specimens in captivity is proposed in order to palliate the high rates of endogamy.

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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.

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The study of two speimens of Gallotia simonyi, that were captured on Roque de Fuera (Anaga, Tenerife), has confirmed the presence, up to fairly recent times, of the last population of this species on the island of Tenerife. The mentioned population has been completely exterminated within the last 50 years by man.

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Wild-caught specimens of the highly endangered giant lizard Gallotia simonyi, which is endemic to the Canary Island of Hierro, were examined for sarcosporidian parasites. One of the animals exhibited sarcocysts measutring 540 (range, 400-720) x 170 (range, 130-220) µm in the musculature of its tail. Feeding of these sarcocysts to a laboratory-reared G. simonyi resulted in the excretion of sporulated sporocysts measuring 8.8 (range, 7.8-9.4) x 6.9 (range, 6.2-7.8) µm. Following experimental transmission. I used light and electron microscopy and identified this parasite as Sarcocastis simonyi sp. No., which displays a dihomoxenous life cycle.

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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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The cliff of Fuga de Gorreta on Hierro ist the last retreat of Gallotia simonyi. During a visit of the island in 1982 the author followefd old and new hints at the present and former occurrence of the lizard. However, it was not possible to document the present existence of the species outside the Fuga de Gorreta. In addition caves and concheros of the Guanches were investigated with respect to skeletal material. Several remains of lizards were found, some dentalia indicating a considerable size of the lizards. The findings also indicate that the lizards were eaten by the aboriginals. – Past and present records (woth one exception) are restricted to regions of old basaltic rocks. – From this understanding I propose to favour the following regions for re-introduction programs of Gallotia simonyi, especially in the case of successful captive breeding: 1) Southern slope Bco Los Cardones, 2) Southern slope Risci de los Herrenos, 3) Southern slope Bco of Tinor, 4) Smaller Zalmor Rock, and 5) Southern slope Bahia de los Reyes.

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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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Review of the herpetofauna of the island of Hierro, where the following species occur: Hyla meridionalis, Rana perezi, Tarentola delalandii ssp., Chalcides viridanus ssp., Gallotia simonyi, and Gallotia galloti caesaris. T. delalandii, C. viridanus, and G. galloti caesaris were captured. Data concerning habits and distribution are presented. It is likely that T. delalandii and C. viridanus represent subspecies characteristic for Hierro. Variation of certain characters in G. galloti caesaris is correlated with its vertical distribution. In some localities this species is extremely abundant. Unfortunately, the large and endangered G. simonyi was not observed. Chances of its survival are discussed. Activities to preserve this lizard from extinction are suggested.

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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.

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A journey to Hierro, Canary Islands, made by W. BINGS had the intention to search for the lizard Lacerta s. simonyi, which already was believed tobe extinct. 1. Informations by the natives on this animal are extensively reproduced and thus secured. 2. The finding of an about two years old skeleton demonstrates the survival of the lizard until today. 3. The capture of a living couple is reported, which unfortunately could not be brought to Germany. 4. Some factors seemingly important for the survival of the lizard also in future are discussed; especially the following key-words: Interspecific competition, commen- salism with seabirds (coprophagy), predators (esp. Tangier raven) and factors caused by human influcnce (e. g. decimation of seabirds, tourism). 5. The urgent necessity for ecological investigations in the field as well as in captivity is pointed out. An appeal for protecting this unique and still poorly known reptile is formulated.

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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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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.

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Bericht über einen Knochenfund auf Hierro, Kanarische Inseln, der einem frühmittelalterlichen Abfallplatz der Ureinwohner entstammt. Bemerkenswert sind zahlreiche Eidechsenknochen, unter denen sich auch Reste der heute fast ausgestorbenen Gallotia simonyi befinden, und die die einst weitere Verbreitung dieser Art auf der Insel belegen. Dies ging bisher nur aus mittelalterlicher Berichten hervor.

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The only known recent locality of Gallotia simonyi near Frontera on Hierro, Canary Islands, was visited at the end of March. At this time of the year the vegetation has only just started to develop. A list is provided of recognized and potential food plants for this mainly vegetarian species. Remarkably, most of these are ligneous and seem to have a low nutritional value. However, recent work indicates that later in the year the herbaceous plant Psoralea bituminosa is the major food item in the diet of adults. The leguminosid plant was only just budding on the rock face in March. A strong sea wind combined with frequently overcast skies made the area inhabited by this species, 300-500 m on the south-west facing exposed cliff, although ambient temperature there ranged between 12 and 32°C. The annual active period of G. simonyi extends from the end of March to early autumn, when the lizards gradually start hibernating. Peak activity occurs in early summer. Ever at this time the animals appear lethargic and they are very shy; this may be an energy saving tactic due to the harsh conditions. Mating lasts a few minutes with the male biting in the side of the female´s neck, as is common in Gallotia. Oviposition in the study area occurs between 29 May and 30 July. On only one occasion did a female produce two clutches in one year, the second of which did not survive long. The first clutch of young females typically usually lay twelve eggs on average, fifteen being the maximum recorded. Soon after the moment of laying, the size of the eggs ranges between 19-21x26-31 mm. Incubation takes 60-70 days at 29°C. A constraint on population growth could be the scarcity of suitable oviposition sites.

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Der einzige bekannte rezente Standort von Gallotia simonyi, nahe Frontera auf Hierro, Kanarische Inseln, wurde Ende März besucht. Zu dieser Jahreszeit hat die Vegetation gerade begonnen, sich zu entwickeln. Eine Liste der erkannten hauptsächlichen Futterpflanzen dieser überwiegend vegetarischen Art wird vorgestellt. Außergewöhnlich ist, daß die meisten von ihnen verholzt sind und scheinbar einen geringen Nährwert haben. Neuere Arbeiten belegen jedoch, daß später im Jahr die krautige Pflanze Psoralea bituminosa der bedeutendste Nahrungsposten der erwachsenen Tiere ist. Dieser Hülsenfrüchter war im März in der Felswand nur knospend. Strenger Seewind, kombiniert mit häufig bewölktem Himmel, ist charakteristisch für den Lebensraum dieser Art, 300-500 m hoch gelegen an einer nach Südwesten exponierten offenen Felswand, mit kühlen Umgebungstemperaturen zwischen 12 und 32°C. Die jährliche Aktivitätsperiode von G. simonyi erstreckt sich von Ende März bis zum frühen Herbst, wo die Eidechsen allmählich mit der Winterruhe beginnen. Der Höhepunkt der Aktivität liegt im Sommer. In dieser Zeit erscheinen die Tiere of lethargisch, und sie sind sehr scheu. Dies scheint eine energiesparende Taktik gegenüber der rauhen Umwelt zu sein. Die Paarung, mit einem seitlichen Biß des Männchens in den Nacken des Weibchens, dauert einige Minuten und ist Gallotia-typisch. Die Eiablage findet in der untersuchten Gegend zwischen dem 29. Mai und 30. Juli statt. Ein Weibchen zeitigte zwei Gelege in einem Jahr, wovon das 2. Gelege nicht lange überlebte. Das 1. Gelege von jungen Weibchen besteht normalerweise aus 4 Eiern, während ältere Weibchen üblicherweise durchschnittlich 12 Eier legen; 15 Eier sind als Maximum dokumentiert. Kurz nach der Ablage sind die Eier 19-21x26-31 mm groß. Die Inkubation dauert 60-70 Tage bei 29°C. Eine Beschränkung des Populationswachstums kann die Knappheit geeigneter Eiablageplätze sein.

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Animals raised in captivity during several generations may not express appropriate antipredator behaviour when reintroduced into the wild. Here we present the results of experiments to enhance behavioural responses to predators in adult males of the endangered lizard Gallotia simonyi (El Hierro, Canary Islands). Individuals were subjected to a training procedure (control, pre-training, training and post-training phases) using stuffed specimens of a kestrel and a cat as predators. We filmed all trials and compared relative durations of the more common behaviour patterns shown by lizards, both among experimental phases and before and after presentation of the stuffed predator. Locomotion and Basking were significantly reduced in the training and post-training trials and also after stimulus presentation, suggesting that the training protocol induced lizard avoidance over both predator models. To our knowledge, this is the first time lizards have been trained to show antipredator avoidance and our results provide the basis for a new management strategy that could be useful for reintroduction of captive-bred individuals of endangered species.

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Since 1986, the insular, endangered Hierro Giant Lizard (Gallotia simonyi machadoi: Lacertidae) has been subjected to captive breeding for conservation purposes at El Hierro (Canary Islands). Due to the lack of a reintroduction plan, presently the captive stock probably outnumbers the wild population of the species, which only occurs at a steep cliff within the island. For the first time, two adult males, fitted with radiocollars, were freed in the wild. The lizards were released at La Dehesa, a pre-selected sit devoid of current populations of the species, but belonging to its historic range as evidenced by plenty of subfossil remains. The study was aimed to test whether the captive reared lizards are good subjects for a reintroduction program, and whether the selected area still suits well their ecological requirements. For months, both lizards stayed close to the release plot, dug burrows and found food. Body weight losses during the dry season were overcome in the following humid seasons, as food availabity improved. Activity cycles and feeding were favoured by better thermal conditions than those experienced by the wild and captive populations. Adter 140 days, one of the lizards was killed by a feral cat, as has been shown to happen in the wild population. Our results shows that the extant wild population of G. simonyi bears sub-optimal ecological conditions. A reintroduction of captive reared lizards in well preserved habitats of the islands in both recommendable and feasible, provided that a feral cat control program is undertaken.

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A sub-fossil deposit located in Hierro Island (“Playa de la Arena”) at the beginning of the Middle Ages, displays among other animals, bones of lizards. According to bone histological criteria, it can be determined that two species of lizards are present in this deposit. Bones of various sizes come from a large sized species, probably Gallotia simonyi. The oldest specimen observed in our sample was at least 14 years old. Other bones come from lizards of little size, probably G. g. caesaris. The oldest specimen collected was 6 or 7 years old.

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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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Two mummified specimens of the extinct giant lizard Gallotia goliath have recently been discovered in the island of Tenerife (Canary Islands). For the first time they allow the study of the species` external morphology. It is characterized by its large size (estimated length >1,5 m) and a low number of temporal scales. Pholidotic characteristics and the dentition provide evidence for a closer relationships between G. goliath and G. simonyi, a species which has recently disappeared from the Roque Chico de Salmor but has survived on the island of El Hierro. Gallotia goliath probably became extinct in Tenerife as a consequence of habitat perturbations resulting from human impact and the introduction of new predators. Also, competition between juvenile giant lizards and adults of the smaller species G. galloti may have contributed to the decline of the giant lizard.

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One of the numerous factors suggested for the decline of the giant lizard of El Hierro (Gallotia simonyi) is the competition with the smaller congener, G. caesaris, ubiquitous throughout El Hierro. Experiments were conducted to determine the potential for interference competition amongst G. caesaris and adults and juveniles of G. simonyi. Movement patterns and activity levels of individuals were quantified. No interspecific aggressive interactions were observed, however, distance moved and activity of G. simonyi changed as a result of the addition of conspecifics and of individuals of the smaller,more active, species. These results suggest that the presence of G. caesaris has the potential to influence behavior and energetics of G. simonyi. Interestingly, a similar species association exists on the nearby island of Gran Canaria, in which a large and numerous lizard G. stehlini is geographically sympatric with a smaller species, G. atlantica. Interspecific aggressive interactions (including predation!) were observed in G. stehlini towards G. atlantica, and distance moved and activity of G. stehlini did not change in presence of G. atlantica.

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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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Avian predation is likely to be a relevant pressure on the populations of lizards of El Hierro (Canary Islands), particularly if we consider that kestrel (Falco tinnunculus) is extremely abundant on the island. We investigate the potential predation pressure on G. simonyi by studying the diet of F. tinnunculus estimated through the analysis of pellets, and by measuring predation pressure estimated by attacks to plasticine models. We also address the question of wheather there is a size refugium for large lizards in relation to avian predators. F. tinnunculus appears to be the only potential avian predator of G. simonyi. Lizards are a substantial portion of the diet of the kestrel although predation pressure upon models was not high. The only site where high predation pressure was detected in the plasticine models is the natural habitat of the relictual extant population of G. simonyi. In this habitat however, models of large lizards were attacked significantly less than models of small lizards. A study of the diet of F. tinnunculus from the Iberian Peninsula in a habitat with a dense population of Lacerta lepida – a lizard of similar size as G. simonyi – shows that adult lizards are not predated by kestrels either.

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We report selected body temperatures (Tb) and thermal set-points ranges (Tset) of males, females and juveniles of Gallotia simonyi. This information may contribute to improving captive population conditions and to select reintroduction areas of this endangered species. We also report thermal requirements of sympatric G. caesaris and of two other species of this endemic genus from the Canary Islands: G. stehlini and G. atlantica. Mean body temperature of G. simonyi is 35.6°C (Tset: 32.4 – 38.3°C), similar to those other Gallotia species studies. Juveniles of G. simonyi selected higher temperatures than adults, and G. stehlini had no intraspecific differences, juveniles of G. caesaris selected lower temperatures than adults. The lizards from the Island of El Hierro appear to be more thermophylous than the other two species.

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The giant lizard of El Hierro, Gallotia simonyi, is perilously close to extinction. Here we describe 51 categories of resenzia for this endangered species grouped in five classes; maintenance, locomotory, feeding, social and reproductive. Reproductive behaviour showed peculiar patterns involved on plant material consumption. However, even under resenzia conditions, Gallotia simonyi exhibited low levels of lovomotor activity and decreased levels of aggressiveness compared to other Gallotia species in the Canary archipelago. Agonistic behaviour was only observed in juvenile individuals. These observations are consistent with the mild temperament of Gallotia simonyi, which may be related to the prolongued captivity of the adults.

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Lizards use chemical cues to locate and identify prey and plant food, assess the nutritional quality of food, and detect plant toxins. Among insectivorous lizards, all actively foraging species studied respond strongly to prey chemicals sampled lingually, but ambush foragers do not. Much recent research has been devoted to assessing differential responses to food and nonfood chemicals (i.e., food-chemical discrimination) by omnivorous and herbivorous species and determining whether correlated evolution has occurred between plant diet and plant-chemical discrimination. We conducted experimental studies of food-chemical discrimination by two species of teiid lizards, the omnivorous Cnemidophorus murinus and the actively foraging insectivorous Ameiva ameiva. The omnivore distinguished both prey and plant chemicals from control substances. The insectivore exhibited prey-chemical, but not plant-chemical, discrimination, as indicated by tongue-flicking and biting. A comparative analysis using concentrated-changes tests showed that correlated evolution has occurred between plant consumption and plant-chemical discrimination in a major lizard taxon, Lacertiformes. These results extend and strengthen previous findings of similar correlated evolution to a new group and add to a growing database indicating that omnivorous lizards use chemical cues to assess both prey and plant foods.

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We studied lingual and biting responses to food chemicals by two species of omnivorous lacertid lizards, the Canary Island endemics Gallotia simonyi (the giant lizard of El Hierro) and Gallotia caesaris (Boettger`s lizard), to ascertain their ability to discriminate between prey and plant food chemicals on the one hand and control stimuli on the other. We recorded frequencies of tongue-flicking and latency to bite in 60-s trials in which chemical stimuli on cotton-tipped applicators were presented to the lizards. Both species exhibited prey-chemical discrimination, as indicated by elevated tongue-flick rates and higher proportions of individuals biting in response to surface chemicals from crickets. Both species exhibited plant-chemical discrimination, as indicated by significantly greater tongue-flick rates and biting frequency in response to chemicals from tomato fruit than to the control stimuli. Juvenile G. simonyi responded much more strongly to chemical stimuli from tomato fruit than from leaves of Psoralea bituminosa, which is not a preferred food for juveniles. The findings are consistent with the hypothesis that chemosensory discrimination evolves in omnivorous lizards to permit evaluation of food quality, resulting in correspondence between plant diet and plant-chemical discrimination, both being absent in insectivores. The results are also consistent with the hypothesis that prey-chemical discrimination is retained and plant-chemical discrimination evolves in the omnivorous lizards derived from actively foraging insectivores.

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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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Feral cats are introduced predators spread all over the canary archipelago. Their possible role in the extinction processes undergone by the endemic fauna was investigated by comparing the impact of cat predation on Gallotia simonyi, a big sized, endemic lacertid lizard close to extinction, whith that experienced by other native and introduced species at two sites on El Hierro island. The sympatric, small and widespread G. caesaris, with different life history traits, sourced a good control for comparisons. A general approach to food habits, spatial patterns and activity patterns of feral cats was devised to achieve conclusions. Ecological and social adjustments were similar to those described in other feral populations previously studied. Cats showed a strong dependence on the availability of rabbits. Evidence was found that cats also selected Gallotia lizards as preferred prey, irrespective of their aboundance. Nearly extinction of G. simonyi seems resenzia o largely in terms of predation pressure exerted by cats, and the present day known population is certainly threatened by cats. Hence, feral cat control is invoked as a necessary measure to save the giant lizard from extinction, and recover its former island-wide range.

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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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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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Due to increasing number of animal species in danger of extinction, captive breeding of individuals has become a necessary procedure for many recovery programs. As specimens born and raised in captivity during several generations may not develop some behavioral and performance aptitudes properly, several types of training are useful to apply before releasing them into the wild. We present here the results of experiments aiming to detect the effect of daily running trials in young males of the endangered lizard (Gallotia simonyi) from El Hierro (Canary Islands). We made individuals run in a racetrack twice every day, for five days a week between the end of July and the end of September. We filmed all running trials and calculated running speed for each individual dividing the distance run by the time used. Running speed did not correlate with body condition of the lizards but there was variation in running speeds of some individuals with similar body conditions. Running speed of lizards used in the experiments significantly increased along the whole trial period. By contrast, mean running speed did not change significantly in a control group, participating twice in running trials, one at the beginning and the other at the end of the experimental period. From these results we suggest that locomotor training contributed to increasing final running speeds of experimental lizards.

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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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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.

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A new deposit of giant lacertids is described from a volcanic cave in the western part of El Hierro island. On the basis of an analysis of the 388 pieces found in this deposit, using both the literature and osteological material from Tenerife and El Hierro, it is concluded that three different species are represented: Gallotia goliath (Mertens), now extinct in the Canary Islands, Gallotia simonyi (Stein.) and Gallotia galloti caesaris (Lehrs). The two last species are still present on the island. The presence of G. goliath in this deposit represents the first record of this species in the island of El Hierro.

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In the frame of the project “Recovering of the El Hierro Giant Lizard, Gallotia simonyi” (Life Program no. B4-3200/94/743)” the possibility of expanding the present range of distribution has been foreseen. The place chosen (la Dehesa) is situated in the west of El Hierro island. The vegetation is composed of Juniperus forest not much affected by human influence. Although the El Hierro Giant Lizard (Gallotia simonyi) is mainly a herbivorous species, its diet is completed by consuming preys, mainly arthropods. Monitoring throughout an annual cycle was carried out in order to evaluate in a reliable way the suitability of the area as a possible place for releasing lizards. The evolution of trophic resources (animal) was analyzed by means of monthly biocenometers. The results obtained show that the resources consumed by the natural population of El Hierro Giant Lizard are represented. Both, prey number and biomass available are scarce throughout the year but they are considered enough for fulfilling the trophic requirements of an introduced populations since they play a complementary role in its diet. On the other hand, the size classes of the arthropods present fall within the range consumed by the lacertids of such body size.

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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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Paleontological and archaeological evidences coming from 39 sites of El Hierro (Canary Islands) show that the herbivorous, bog sized and endangered G. simonyi (Lacertidae) was formerly tied to the xeric and thermophyllic ecosystems all around the island. Sadly for conservation concerns, most of this landscape has been strongly perturbed by man. 14C dating revealed that in currently well preserved habitats of this kind at La Dehesa, some populations faded out not before the 19th century. The taphonomical traits of many subfossil findings strongly suggest for feral cats (probably) introduced after the resenzi conquest) playing a role in these extinctions. Except for the occurrence of cats (which also threaten the small wild population), La Dehesa juniper scrubland/woodland appears as a priority place for the reintroduction of captive bred lizards.

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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 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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Many lizards use femoral gland secretions in reliable intraspecific communication. Based on mass spectra, obtained by GCeMS, we found 57 lipophilic compounds in femoral secretions of males and females of El Hierro giant lizards, Gallotia simonyi (fam. Lacertidae). Compounds included steroids (mainly cholesterol) and fatty acids ranging between n-C16 and n-C22 (mainly hexadecanoic and octadecanoic acids), followed by aldehydes, alcohols, ketones, squalene and waxy esters. There were important intersexual differences in thepresence, abundance and number of compounds (more numerous in males). Males had higher proportions of the most odoriferous compounds (fatty acids and aldehydes), while females had higher proportions of more stable compounds (steroids, waxy alcohols, waxy esters and terpenoids). This suggests sexual differences in function of femoral secretions. In addition, some compounds could reflect the physiological state, allowing monitoring health of lizards from secretions samples, which is especially important given the critical conservation status of this lizard.

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This paper presents the first data on the ecology of the Giant Hierro Lizard (Gallotia simonyi simonyi) from Canary Islands; this animal was believed to be extinct until its recent finding, in 1975. The biotope, a very steep rocky cliff, almost inaccessible in many places, is described; the climate of the area is subdesertic and the plant cover, very sparse, is xerophytic; the vertebrate fauna is poor, but insects are abundant and diverse. The colour of this lizard is almost black, with large dull grey patches at the sides in the adults, while in the youngs the colour is earthly brown with whitish dorsal stripes. The largest specimen we measured was near 70 cm from snout to tail`s end. Daily activity begins in young specimens when the sun reaches the area, while in the adult ones activity begins somewhat later, even at noon for the oldest animals. The diet consists entirely of plants, and includes lignified stems and other non-nourishing parts from several species (Kleinia neriifolia, Lavandula abrotanoides, etc.). Obviously there exists a strong intraspecific competition for food. The number of animals was very low in September 1975, about 200 specimens, half of them or more being young. This number might have been increased by now through protective measures recently adopted. Nevertheless, the status of the population is still critical and the danger of its extinction is strong. Some recent plans to modify the area, building industrial facilities nearby, may have, of course, very bad effects on this lizard.

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This paper presents the first data on the ecology of the Giant Hierro Lizard (Gallotia simonyi simonyi) from Canary Islands; this animal was believed to be extinct until its recent finding, in 1975. The biotope, a very steep rocky cliff, almost inaccessible in many places, is described; the climate of the area is subdesertic and the plant cover, very sparse, is xerophytic; the vertebrate fauna is poor, but insects are abundant and diverse. The colour of this lizard is almost black, with large dull grey patches at the sides in the adults, while in the youngs the colour is earthly brown with whitish dorsal stripes. The largest specimen we measured was near 70 cm from snout to tail`s end. Daily activity begins in young specimens when the sun reaches the area, while in the adult ones activity begins somewhat later, even at noon for the oldest animals. The diet consists entirely of plants, and includes lignified stems and other non-nourishing parts from several species (Kleinia neriifolia, Lavandula abrotanoides, etc.). Obviously there exists a strong intraspecific competition for food. The number of animals was very low in September 1975, about 200 specimens, half of them or more being young. This number might have been increased by now through protective measures recently adopted. Nevertheless, the status of the population is still critical and the danger of its extinction is strong. Some recent plans to modify the area, building industrial facilities nearby, may have, of course, very bad effects on this lizard.

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The objewct of this study was to examine the erythrocytes, leukocytes and thrombocytes of the giant lizard of El Hierro (Gallotia simonyi) by light and electron (TEM) microscopy, and cytochemical staining. Smears were prepared from blood from the ventral coccygeal vein of 10 healthy adult lizards (five males and five females) from the Giant Lizard of El Hierro Reproduction and Research Centre, Canary Islands, Spain. The cytoichemical stains used were: benzidine peroxidase (BP), chloroacetate esterase (CAE), alpha-naphthyl acetate esterase (ANAE), acid phosphatase (AP), periodic acid-Schiff (PAS), toluidine blue (TB) and May-Grünwald-Giemsa (MGG). Electron microscopy was also performed on all samples. Heterophils had granules that were heterogeneous in b oth size and electron density, and stained with BP, PAS and ANAE. Eosinophil granules were homogeneously electron-dense and stained for AP, CAE and ANAE. Basophils had both highly and moderately electron-dense granules, and stained with TB and ANAE. Azurophil granules were of low electron-density and stained for AP, CAE and ANAE. Azurophil cytoplasm was vacuolated on TEM. The cytoplasm of lymphocytes contained many ribosomes and was positive for AP. Monocytes had a large nucleus and a vacualated cytoplasm but did not stain by any of the cytochemical methods used. Thrombocytes had a relatively large nucleus but little cytoplasm; they did not stein cytochemically. The blood cells of the giant lizards of El Hierro differ from those of other members of the Order Squamata both morphologically and cytochemically. The variation in cytochemical responses in the blood of reptiles makes it necessary to study species individually if meaningful clinical decisions are to be made.

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Blood samples were taken from the ventral coccygeal vein of 15 El Hierro giant lizards (Gallotia simonyi) (seven females and eight males), six La Gomera giant lizards (Gallotia bravoana) (four males and two females) and four Tenerife giant lizards (Gallotia intermedia) (two males and two females), and 31 blood parameters were measured. Among the haematological parameters there were significant differences between the three species in heterophils, azurophils and lymphocytes, but no significant differences in red blood cell count, white blood cell count, haemoglobin, packed-cell volume, monocytes, eosinophils and basophils. in terms of blood chemistry there were significant differences between the three species in cholesterol, triglycerides, glucose, sodium, chloride, urea, uric acid, total proteins, prealbumin, albumin and gamma globulins, but no significant differences in calcium, potassium, aspartate aminotransferase, alanine aminotransferase, creatine kinase, bile acids, alpha-i and alpha-2 globulins and beta globulins.

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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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The Hierro Giant Lizard (Gallotia simonyi) is themost threatened reptilian in Europe. In the present paper we present the results obtained during the first year of action within the recovery plan of the species designed and advanced by the Spanish Herpetological Society (AHE) and the Regional Government of the Canary Islands. Believed to be extinctand rediscoveredin 1975, the Hierro Giant Lizard has at present only a small population of scarcely 150 specimens livingin the area called Fugade Gorreta in the island of EI Hierro ( Canary Islands). To avoid its extinction, reproduction of captive specimens has been achieved, and the basic studies have been performed to contemplate its reintroduction in other suitable areas. At present a number of animals born in captivity is available (130 specimens), from which new population groups maybe established to allow the species to recolonize the areas it formerly occupied in the island.

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Roque Chico de Salmor (Canary Islands) surveys: 1. possible causes for the extinction of its Gallotia simonyi population; 2. the systematic status of its Tarentola. The vegetation of the rock (close to El Hierro) has declined strongly during the last decades, presumed due to the increasing number of herring gulls (Larus argentatus atlantis); this ecological change is seen as a possible cause for the extinction of its population of Gallotia simonyi STEINDACHNER, 1889. The geckoes of this isolated rock are clearly Tarentola boettgeri hierrensis (JOGER & BISCHOFF, 1983) and not Tarentola delalandii (as presumed anteriorly).

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In the frame of the project “Recovery of the El Hierro Giant Lizard” (Life Program B4-3200/94/743) the possibility of expanding the present range of distribution has been foreseen. One of the places chosen (La Dehesa) is situated in the west of el Hierro island. The vegetation is composed of Juniperus forest not much affected by human influence. The area was selected because of several reasons: the finding of fossil remains of giant lizards, its remote situation far from human influence, the good plant coverage and the present of potential shelters. Monitoring was carried out in order to evaluate in a reliable way the suitability of the area as a possible place for releasing lizards. The evolution of trophic resources (vegetation) was analyzed by means of monthly transects. The results allow to value this area positively as a zone for expanding the range of the lizard, since it resenz the necessary condition for supporting a lizard population. The lack of water during the dry seasons is minimized by the water contained in the vegetation. The carrying capacity of La Dehesa expressed in minimum lizard density and calculated from the plant biomass available would vary between 67.64 and 101.46 adult individuals by hectare.

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Endangered and close to resenzia , the giant lizard of El Hierro (Gallotia simonyi) is the subject of a recovery plan based on captive breeding and eventual reintroduction into native habitats. This endemic species is largely herbivorous and in captivity bred resenzia o on a diet that was nutritious but not based on native foods. One goal was to change the dietary habits of a group of G. simonyi maintained in the Centro de Recuperación del Lagarto Gigante de El Hierro, so that hey could safely be reintroduced into natural habitats. Thus, a controlled period of adaptation to the natural vegetation of the reintroduction area was established. In captivity they had received water ad libitum, but in the dry natural area water is only occasionally available as condensation or rain. Our results indicate that the animals can consume and do well on the native resources available in the reintroduction area, particularly fruits of Juniperus resenzia, which are produced throughout the year. Lastly, we include dietary recommendations for lizards born in captivity which will ultimately be reintroduced into native habitats.

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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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At a meeting with various specialists, the current situation as well as the future prospects for the reintroduction of the giant lizard of El Hierro (Gallotia simonyi) in the natural habitat were discussed. A survey of the two habitats, La Dehesa and El Julan, where captive bred Gallotia simonyi had been reintroduced, revealed disappointing results as only very few specimens were found again. However, the population size of the reintroduced lizards on the Roque Chico de Salmor is satisfactory. In addition the factors for a successful reintroduction are listed.

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The structure of the free-living population of the Giant lizard of El Hierro (Canary Islands, Spain) has been studied. The population seems to be composed of 83 juveniles, 45 females and 22 males, that gives an effective population size of N = 59.10. But, if females reach sexual maturity at larger body sizes, corresponding to an age of six years, as it seems the case in captivity individuals, the effective population size would drop to N = 29.33. We also observe a sex-ratio bias towards females, as well as a lower proportion of juveniles than expected. The possible causes of this population structure are discussed. Gallotia simonyi shows a clear sexual dimorphism in body size, as well as a significantly slower growth rate than other lacertid lizards of similar body size. We did not observe significant differences in the condition state of individuals from lower and higher altitudinal parts of the distribution area.

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Es werden Reiseeindrücke von einem Besuch der Rieseneidechsen (Gallotia intermedia) bei Guaza im Süden von Teneriffa, der in La Laguna gehaltenen Rieseneidechsen (Gallotia intermedia) aus dem Teno-Gebirge und der Hierro-Rieseneidechsen (Gallotia simonyi) auf der Insel El Hierro nebst einigen Anmerkungen und Informationen vom April 2006 geschildert.

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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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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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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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From 20.4.-26.4.2015 as well as from 14.4.-26.4.2016 we visited the Canary Island of El Hierro. Our particular interest was directed towards the El Hierro giant lizard (Gallotia simonyi) and Boettger’s lizard (Gallotia caesaris caesaris). With our pictures of the Mediterranean Tree Frog (Hyla meridionalis) from the plateau near Tiñor, we are finally able to give proof of its existence on El Hierro.