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In the Canary Islands five extant and two extinct giant lacertid lizards belonging to the endemic genus Gallotia are known. A comparative study of the living and subfossil specimens from the Western Canary Islands demonstrates that the extinct giant species Gallotia goliath and Gallotia maxima are synonymous with the living Gallotia simonyi. Characters formerly used in the diagnosis of the extinct species and subspecies fall within the range of intraspecific variation (ontogenetic and individual) of the living species. The only significant difference between living and subfossil populations of G. simonyi is size, and there is strong evidence to suggest that the reduction in size in living populations reflects shorter life expectancy, a factor that should be taken into account in the current conservation projects on this species.

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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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Qualitative and quantitative comparisons of histological data recorded from growing bone from seven extant and extinct taxa of Gallotia show that these lizards do not have the same longevity, reach sexual maturity at various ages and probably have different growth rates which are in reverse proportion to the specific size of individuals in each taxon. In term of relative growth, the highest rate is seen in the smallest taxon (G. atlantica) and the lowest in the largest taxon (G. goliath). It appears that differences between the maximum size reached, irrespective of the size of hatchlings, are only the consequence of changes in longevity allowing a more or less protracted growth; they are not due to differences in growth rates. On the basis of these data we discuss some points relating to adaptive strategies and evolutionary features of these lizards.

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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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The endemic Canary Island lizard clade Gallotia, which includes the largest members of Europe`s dominant reptile group, Lacertidae, is one of the classic examples of insular gigantism. For the first time we use fossil data to test the evolutionary reasons for the association between gigantism and herbivory. We describe an almost completely preserved skeleton of Janosikia ulmensis comb. nov. from the early Miocene of Ulm, Germany (MN 2a, ∼ 22 Mya). We show that this species and Oligocene Pseudeumeces cadurcensis (Filhol, 1877) are in fact crown lacertids, and the first known pre-Quaternary record of the total clade of Gallotia. Pseudeumeces confirms the early origin of crown Lacertidae in the Palaeogene of Europe. More importantly, these fossil taxa show that large body size was already achieved on the European mainland by the early Miocene. Furthermore, Pseudeumeces and Janosikia were faunivorous, thus demonstrating that insularity, not large body size, was crucial to the evolution of herbivory in this lineage. Body size change in Gallotia was more complex than previously thought, encompassing size increase [e.g. in the extinct Gallotia goliath (Mertens, 1942)], but more commonly involving miniaturization. The physical environment may play a crucial role in modulating the evolution of body size in this natural laboratory. © 2015 The Linnean Society of London

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We used carbon (_13C) and nitrogen (_15N) isotopes to examine the foraging ecology of Tenerife giant rats (Canariomys bravoi) and lizards (Gallotia goliath) in northwestern Tenerife, which until recently, were the island’s largest terrestrial vertebrates. We combined new isotope data for 28 C. bravoi and 14 G. goliath with published regional data for both species and then compared these with data for co-occurring extant taxa and modern C3 plants. Isotope data suggest both extinct species relied primarily on C3 resources and were trophic omnivores. However, the two species appear to have partitioned their resources when living in sympatry. Isotopic overlap between C. bravoi and Rattus spp., and between G. goliath, extant Gallotia galloti, and introduced rabbits (Oryctolagus cuniculus) suggests reliance on similar foods. We radiocarbon dated four C. bravoi and two G. goliath with the most extreme isotope values. These new dates do not settle the question of what triggered the demise of either species. Nevertheless, the data are most consistent with anthropogenically-induced extinction. Temporal isotopic trends contradict expectations if regional climate were responsible, and confidence intervals for radiocarbon dates suggest it is highly likely that both species were present when humans first settled the island.

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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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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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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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En el presente trabajo se describe un nuevo yacimiento de restos esqueléticos subfósiles de dos especies de vertebrados extintos del Terciario-Cuaternario de las Islas Canarias: Lacerta maxima Bravo, 1953 (Sauria: Lacertidae) y Canariomys bravoi Crus. et Pet., 1964 (Rodentia: Muridae), encontrados en una cueva de naturaleza volcánica en la zona alta de Icod de los Vinos (Tenerife).

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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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The genus Gallotia is an endemic lizard clade from the volcanic archipelago of the Canary Islands (Spain). This clade has five extant and extinct giant species distributed over just five islands in the archipelago: El Hierro, La Gomera, La Palma, Tenerife and Gran Canaria. On the island of El Hierro, remains of several giant species of Gallotia have been found. In this paper, we present a revision and description of the bones from El Hierro with similar osteological characteristics to the giant species from Tenerife, Gallotia goliath. The fossil remains of 24 individuals have been found in volcanic tubes of a Chibanian/upper Pleistocene-Holocene age (Quaternary). These remains confirm the presence of the species Gallotia goliath on the island of El Hierro and provide the first evidence of the possible coexistence of two giant fossil species of Gallotia on the same island. The existence of individuals of Gallotia goliath would imply on the one hand dietary specialization each giant species. On the other hand, it would suggest the transfer of non-flying species between islands raising the possibility that the great landslides of the Quaternary may have played an important role in inter-island migrations.

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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 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).