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A species meets its range limit if the climatic condition favourable for the species exceeds its physiological limits or if it is controlled by biotic interaction of competitor or limited by dispersal and demographic stochasticity or gene flow. Not all species can fully exploit the potentially suitable habitat available to it. Only a few may be capable of ranging throughout its suitable habitat while most of the species give up their distribution far before its potential range. Biotic mode of range limitation is very rare. Restricted gene flow contributes to limit the distribution of a species in most cases. A set of environmental variables or a single variable may induce restriction of gene flow into a population thereby limiting the range. With the advent of advanced molecular method and integration of population genetics and landscape study, it has been possible to check various hypothesis of range limit due to gene flow. With this concept, a candidate set of environmental variables to predict the distribution of P. cretensis, a Cretan endemic reptile with no known apparent reason for range limit. The working hypotheses are to know if the species meets its range limit in response to abiotic variable or if the restricted gene flow is contributing towards range limit. An ensemble species distribution approach was used to compare the potential distribution and the realized distribution. The environmental data was converted into appropriate cost raster to determine an accumulated cost distance and resistance distance. The cost distances were correlated with genetic distance calculated using a set multi-loci nuclear microsatellite gene to establish the relationship between environmental cost and gene flow. I found that the present distribution is below the potential range and abiotic variable is not the cause of the range limit. Also, the study did not find any significant relationship between selected variables and gene flow. The environmental variables used was found to be too coarse to have an impact upon the species. Use of micro-habitat scale environmental predictors and introduction of biological interaction and mechanistic models into SDM can help to solve the even curious case of P. cretensis.

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The evolution of the species Podarcis ehardii in the Mediterranean region saw the formation of many isolated populations that are still in the process of characterization. Given the differences in habitat, different strategies would be adopted in order to escape predation: from cryptic mimetism to escape. In this project a newly described species, Podarcis cretensis, is approached in order to understand how it reacts to a variation in predation pressure during summer (July) and during autumn bird migration (October). Four populations from Crete have been sampled: one on Chrysi islet and three on the main island of Crete (Balos, Elafonisi, Theriso). The experiment was performed during morning and evening activity peaks. The individuals were slowly approached by a walking operator until eliciting a response. Data regarding fleeing distance (FD), approaching distance (AD), refuge type, hiding times, tail condition and age of the individuals were recorded. The results showed that there is a significant overall variation in the distances covered in summer and in October for both AD and FD as well as higher percentage of lizards showing regenerated tails in October compared to July. A significant variation among the four populations is also present for what concern FD and AD. These results show that there is a significant variation in the distances that lizards are willing to cover in the two different periods and in the four populations taken into consideration. This is a clear indication that bird predation has an important effect in shaping the behaviour of island lizards that lack other major predators. The presence of a higher percentage of regenerated tails in populations in October can imply that the sacrifice of the tail is a successful defensive mechanism against bird predation.

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The wall-lizard Podarcis cretensis is distributed on the island of Crete and its surrounding islets. The taxon was recently elevated to the species level due to the fact that the Cretan populations (P. erhardii in that time) were paraphyletic with respect to P. peloponnesiacus. Here, we employed both microsatellite loci and mitochondrial DNA to examine the population structure and the phylogeographic patterns of the Cretan wall-lizard based on Bayesian Inference approaches. Samples of the species P. levendis, P. peloponnesiacus, and P. erhardii were also included in the present study mainly as outgroup but also as putative source populations. Based on the microsatellite dataset, strong population structure was detected that not only discriminates samples at the species level but also revealed within species population structure for P. cretensis and P. peloponnesiacus. The chronophylogenetic analyses place the differentiation of the Cretan wall-lizard at Pliocene probably triggered by the paleogeography of the area, i.e. the Pliocene islands of Crete. Under a holistic approach followed in this study the molecular data were combined with the results of species distribution modelling assisting in the elucidation of the biogeographic history of the Cretan wall lizard.

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A critical review of the evolutionary biology of Iberian and North African lizard members of the genus Podarcis (Lacertidae) based on phylogeny, phylogeography, morphometrics, behavior, ecology and physiology is presented. The Iberomaghrebian region is inhabited by at least 12 different evolutionary lineages that group into a monophyl- etic clade (except Podarcis muralis). In contrast to the current taxonomy, the saxicolous ‘Podarcis hispanica’ is paraphyletic with respect to Podarcis bocagei and Podarcis carbonelli, two currently recognized species. Nodes in the phylogenetic tree are deep, resulting from old divergences, clearly preceding the Pleistocene. Nevertheless, more recent range changes as a result of glaciations are also evident. The most plausible evolutionary scenario for this group indicates both vicariant and dispersal events. Although parapatry between lineages is the rule, sympatry and even syntopy are frequent, but usually between ground-dwelling and saxicolous forms. Contacts between forms with similar habitat use are rare and local. Morphological distinctiveness between lineages has been demonstrated, indicating historical constraints. However, other characters have repeatedly evolved under similar environmental pressures independently of the evolutionary lineage. Strong sexual dimorphism derives from sexual selection and is attained before sexual maturity, although developmental restrictions exist. Variation between popu- lations is also important and derives from local variation in both natural (habitat, climate) and sexual (density) selective pressures. Evidence for short-term changes has already been found, particularly in insular populations. Reproductive isolation between syntopic forms and partner recognition are based on male–male competition and on visual and chemical recognition of females by conspecific males. Despite this ancient diversification, most forms maintain a degree of reproductive compatibility. Hybridisation may occur, but is limited, and there is evidence of selection against hybrids. The ecological analysis presented here does not support exploitative competition, but rather behavioral interference between forms. Ecomorph classification of lineages suggests character displacement between those with extensive range overlap. Finally, a critical assessment of the specific status of all lineages is provided and directions for further research are suggested.

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The Greek lizard fauna consists of 26 species from which 5 are monotypic and the other ones are represented by a total of 86 subspecies. Five species and 61 subspecies are endemic of Greece. A checklist including the geographical distribution of each taxon in the Greek region is presented.

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Lizards and Eleonora’s falcon occur on many Mediterranean islets. Data given in literature and new observations concerning their asymmetrical interactions, which have been reviewed and illustrated, allow to regard those as a commensal relationship typical on these micro-insular ecosystems. Some considerations on the ecological, ecomorphological and phenological traits involved on this commensalism are also briefly discussed.

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Background Lizards of the genus Podarcis are widespread in the Mediterranean region, including islands and island archipelagos. These small-bodied lizards have a predominantly protective green-brown colouration. However, some populations display unusual patterns, in which the colouration is predominantly blue or uniformly black. This study explores the factors that influence this chromatic variation, whether environmental (climate and island conditions) or evolutionary (phylogenetic trait conservatism). The colouration of 1400 individuals (27 species) was analysed in the CIELAB colour space. Results Pagel’s λ indicated that colouration is weakly conserved within phylogenetic lineages. Although the island surface plays a key role in the chromatic variability of these lacertids, geographic isolation and climate hold less influence. The colouration of some small island populations tends to be uniform and dark, possibly due to intense intraspecific competition and lower predatory pressure. Conclusions This study highlights the importance of island populations in understanding the processes that favour the emergence of extreme phenotypes in small ectothermic vertebrates.

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Predictive species distribution modelling is a valuable tool for decision-makers in biodiversity conservation, invasive species monitoring and other natural resource management fields. This study employs one recently proposed modelling technique – Maxent – to investigate the curious geographic distribution pattern of Erhard’s wall lizard Podarcis erhardii on Crete and surrounding islets. The main objective is to find out if this distribution can be explained using a set of environmental variables only. A secondary objective is to test the usefulness of an ASTER-derived land cover variable. Thirdly, the effect of replacing the single point occurrence data with representative ‘natural habitat’ polygons created during fieldwork in the immediate vicinity based on expert knowledge is investigated. A set of 19 environmental predictors is employed together with 75 presence-only records, obtained from the National History Museum of Crete. Results are evaluated using the threshold-dependent True Skills Statistic (TSS), a binomial test and the threshold-independent ROC analysis with AUC. Relative variable importance is assessed based on Maxent’s built-in Jacknife functionality. Multi-annual NDVI is found to be the most important predictor, matching not only areas with high presence but also areas of apparent absence of P. erhardii. While the climate variables cloud cover and actual evapotranspiration rank next, the ground variables altitude and CORINE land cover also contribute significantly to the overall ‘cumulative gain’ of 1.86. The resulting distribution fits the provided occurrence data very well (AUC of test partition = 0.86) and results are highly significant at the sensitivity-specificity-equality threshold (p < 0.001). Western Crete serves as subset for testing the usefulness of ASTER imagery for the purposes of this study at regional scale. The ASTER-derived land cover variable is found to contribute as much unique information to the distribution as NDVI, ranks second in individual ‘cumulative gain’ and increases the overall ‘cumulative gain by over 20%. The replacement of single occurrence points with more representative plot data increases the ‘cumulative gain’ by an additional almost 20%, primarily because this allows to better exploit the discriminative power of continuous climatic variables with 1x1km resolution. The study concludes with the observation that present environmental conditions alone may ‘explain’ the observed curious geographic distribution of P. erhardii on Crete. Furthermore, it recommends the use of ASTER imagery for similar studies, because overlay analysis reveals not only a fairly strong association between ASTER, NDVI and CORINE classes preferred by P. erhardii, but also a much more concise identification.

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The assessment of biodiversity by means that ignore the evolutionary relationships of the living forms can be quite misleading, resulting in the over-evaluation of some morphs and the ignorance of other evolutionary significant units. Molecular phylogeny, which is a potentially powerful tool for the conservation of biodiversity, provides essential evidence for setting conservation priorities on several taxa. Phylogenetic analyses can identify cryptic, genetically distinct lineages as well as non-distinctive lineages earlier perceived as separate taxa. The herpetofauna of the east Mediterranean region, which could be considered as one of nature’s most intensively active evolutionary laboratories, serves as an excellent example. Phylogenetic analyses on several lacertid taxa of this area have revealed cases of hidden diversity, paraphyly, new species and new endemics. In several cases the presence of cryptic species (Podarcis levendis, P. cretensis), species with very restricted distributions (P. gaigeae, P. milensis), paraphyletic (M. guttulta) or even polyphyletic species (O. elegans) were revealed. Such cases impose a considerable revision of the taxonomic views and conservation priorities. Based on these findings, many questions have been answered and certainly new ones have emerged, contributing not only to our knowledge on the east Mediterranean herpetofauna, but to broader issues of conservation biology, prioritizing conservation efforts and enhancing the need for a new multidisciplinary and innovative tool for screening and re-evaluating biodiversity.

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Recently, several works have focused on the lacertid lizards of the genus Podarcis, revealing cases of hidden diversity and paraphyly, and offering evidence that suggests the revision of the extant taxonomical arrangements within the genus. Hidden diversity and paraphyly have been shown to exist in the relationships betweentheBalkan species P. peloponnesiacaandP. erhardii as well. Herewecouple a molecular (mtDNA) dataset with a corresponding morphological one, consisting of morphometric and pholidotic characters, to check for concordance between the two. Phylogenetic analyses reinforced previous suggestions for paraphyly of P. erhardii with respect to P. peloponnesiaca.We found the variation of certain pholidotic characters concordant with the relationships inferred from partial mtDNA sequences, whereas morphometric characters were not. The latter is possibly due to greater influence of morphometric characters by environmental factors. To avoid the observed paraphyly we proceed with the description of the populations from Crete and the islet of Pori, until now designated as P. erhardii, as separate taxa at the species level.

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The consequences of fragmentation may have severe effects on the survival of isolated populations. The importance of this phenomenon is of a major importance in conservation biology and has initiated new disciplines such as conservation physiology and immunoecology. Insularity provides an excellent system for the study of fragmentation. Island`s features, such as area and age, have been reported to exert a direct impact on organisms: genetic diversity is positively correlated with island area but negatively correlated with island age and exactly the same pattern stands for the efficiency of immune system, since the last is depended directly on genetic variation. We worked in a system three islands of Central Aegean that differ in age and area: Naxos, a large (430 km2) and old island (16.350 y.a.), Kopries, a small, young islet (0.3 km2, 4.200 y.a.) and Daskalio, a tiny (0.01 km2) and very young (1.500 y.a.) islet. Genetic variation in these populations is described by the following relenence: Naxos > Daskalio > Kopries. Using this study model, we tried to assess the impact of fragentation on the immune system of Aegean wall lizard (Podarcis erhardii). We expected that reduced genetic variation in small and old islands would impair immune response increasing thus the susceptibility to infections by parasites. We used exclusively adult males in order to eliminate the impact of female particularities (oviposition, gravidity). Infection was made artificially using the hemoparasite Hepatozoon sp., which is a natural parasite of P. erhardii. We have to mention that this parasite comes from another taxon (P. cretensis), that considers as sister species to P. erhardii. We quantified parasite burden through light microscopy in blood smears every 4 days for two weeks. Parasite load was considerably lower in the case of Naxos, suggesting that lizards from this population are able to resist parasite infection. The reverse results were obtained from Kopries where infection was realized easily and quickly whereas the population from Daskalio shows an intermediate response. We believe that our findings could be attributed to the restricted genetic variation of Kopries, due to the small size and the age of the island. Hence island`s features seem to shape immune efficiency as result of decreased genetic diversity.

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Temperature sensitivity of digestive processes has important ramifications for digestive performance in ectothermic vertebrates. We conducted a comparative analysis of temperature effects on digestive processes [gut passage times (GPTs) and apparent digestive efficiencies (ADEs)] in five lacertid lizards occurring in insular (Podarcis erhardii, P. gaigeae), and mainland (P. muralis, P. peloponnesiaca, Lacerta graeca) Mediterranean environments. GPTs were negatively correlated to temperature with mainland taxa having 10–20% longer GPTs than island taxa. In contrast to previous studies that estimate ADEs using bomb calorimetry, we compare ADEs by analyzing discrete efficiencies for lipids, sugars and proteins at three temperature regimes (20, 25, and 30°C); each of these categories produces different results. ADEs for lipids and sugars showed a monotonic increase with temperature whereas ADEs for proteins decreased with temperature. Island taxa had consistently higher ADEs than their mainland counterparts for lipids and for proteins but not for sugars. They are characterized by superior energy acquisition abilities despite significantly shorter GPTs. Their increased digestive performance relative to the mainland species appears to allow them to maximize energy acquisition in unproductive island environments where food availability is spatially and seasonally clustered.

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The ability of an animal to shed its tail is a widespread antipredator strategy among lizards. The degree of expression of this defense is expected to be shaped by prevailing environmental conditions including local predation pressure. We test these hypotheses by comparing several aspects of caudal autotomy in 15 Mediterranean lizard taxa existing across a swath of mainland and island localities that differ in the number and identity of predator species present. Autotomic ease varied substantially among the study populations, in a pattern that is best explained by the presence of vipers. Neither insularity nor the presence of other types of predators explain the observed autotomy rates. Final concentration of accumulated tail muscle lactate and duration of movement of a shed tail, two traits that were previously thought to relate to predation pressure, are in general not shaped by either predator diversity or insularity. Under conditions of relaxed predation selection, an uncoupling of different aspects of caudal autotomy exists, with some elements (ease of autotomy) declining faster than others (duration of movement, lactate concentration). We compared rates of shed tails in the field against rates of laboratory autotomies conducted under standardized conditions and found very high correlation values (r > 0.96). This suggests that field autotomy rates, rather than being a metric of predatory attacks, merely reflect the innate predisposition of a taxon to shed its tail.

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Caudal autotomy is one of the most effective and widespread defensive mechanisms among lizards. When predators grasp the tail, lizards are able to shed it from the point of the attack and further. Numerous factors have been reported to affect tail-shedding performance such as temperature, age, predation pressure, intraspecific competition etc. Interestingly, the impact of sex on tail loss remains greatly understudied. Here, we analyzed tail autotomy performance, simulated in the lab, in 12 species of lacertid lizards belonging to five genera (Algyroides, Anatololacerta, Hellenolacerta, Ophisops, Podarcis). Our aim was to investigate whether sex affects caudal autotomy and/or the duration of post-autotomic tail movement. We failed to detect any effect of sex on tail loss in the species examined. Also, we did not find any sexual impact on the duration of tail movement after autotomy, with a single exception. Our findings suggest that autotomy serves as a defensive tactic equally in both sexes and is used in the same extent.

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Tail autotomy, the self‐induced tail separation from the body, is a common and effective antipredator mechanism in lizards. In this study, we examine the muscle energetics of tail shedding in six lacertid lizard species (Podarcis erhardii, Podarcis peloponnesiaca, Podarcis muralis, Podarcis gaigeae, Podarcis milensis, and Lacerta graeca) from the northeast Mediterranean region. Very long periods of postautotomy tail movement were demonstrated for all species ( min), and differences among species were not statistically significant. Postautotomy tail movement, powered by anaerobic muscle activity, resulted in a strong increase in lactate concentrations and a concomitant depletion of muscle glycogen of exhausted tails relative to resting tails. No significant differences were found in either lactate or glycogen concentrations among the species examined. Duration of movement was negatively correlated with final lactate concentrations. The lack of differentiation in postautotomy energetic physiology in this group of species that have evolved under very different predation environments indicates that postautotomy muscle metabolism involves an overall conservative suite of characters.

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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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Wall lizards of the genus Podarcis (Sauria, Lacertidae) comprise 17 currently recognized species in southern Europe, where they are the predominant nonavian reptile group. The taxonomy of Podarcis is complex and unstable. Based on DNA sequence data, the species of Podarcis falls into four main groups that have substantial geographic coherence (Western island group, southwestern group, Italian group, and Balkan Peninsula group). The Balkan Peninsula species are divided into two subgroups: the subgroup of P.taurica (P. taurica, P. milensis, P. gaigeae, and perhaps P. melisellensis), and the subgroup of P. erhardii (P. erhardii and P. pelo- ponnesiaca). In the present study, the question of phylogenetic relationships among the species of Podarcis encountered in the Balkan Peninsula was addressed using partial mtDNA sequences for cytochrome b (cyt b) and 16S rRNA (16S). The data support the mono- phyly of Podarcis and suggest that there are three phylogenetic clades: the clade A (P. taurica, P. gaigeae, P. milensis, and P. melisell- ensis); the clade B (P. erhardii and P. peloponnesiaca), and the clade C (P. muralis and P. sicula). By examining intraspeciWc relationships it was found that extant populations of P. erhardii are paraphyletic. Furthermore, subspecies previously deWned on the basis of morphological characteristics do not correspond to diVerent molecular phylogenetic clades, suggesting that their status should be reconsidered. The distinct geographic distribution of the major clades of the phylogenetic tree and its topology suggest a spatial and temporal sequence of phylogenetic separations that coincide with some major paleogeographic separations during the geological history of the Aegean Sea. The results stress the need for a reconsideration of the evolutionary history of Balkan Podarcis species and help overcome diYculties that classical taxonomy has encountered at both the species and subspecies level.

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Wall lizards of the genus Podarcis (Sauria, Lacertidae) are the predominant reptile group in southern Europe, including 24 recognized species. Mitochondrial DNA data have shown that, with the exception of P. muralis, the Podarcis species distributed in the Balkan peninsula form a species group that is further sub-divided into two subgroups: the one of “P. tauricus” consisting of P. tauricus, P. milensis, P. gaigeae, and P. melisellensis, and the other of “P. erhardii” comprising P. erhardii, P. levendis, P. cretensis, and P. peloponnesiacus. In an attempt to explore the Balkan Podarcis phylogenomic relationships, assess the levels of genetic structure and to re-evaluate the number of extant species, we employed phylogenomic and admixture approaches on ddRADseq (double digested Restriction site Associated DNA sequencing) genomic data. With this efficient Next Generation Sequencing approach, we were able to obtain a large number of genomic loci randomly distributed throughout the genome and use them to resolve the previously obscure phylogenetic relationships among the different Podarcis species distributed in the Balkans. The obtained phylogenomic relationships support the monophyly of both aforementioned subgroups and revealed several divergent lineages within each subgroup, stressing the need for taxonomic re-evaluation of Podarcis’ species in Balkans. The phylogenomic trees and the species delimitation analyses confirmed all recently recognized species (P. levendis, P. cretensis, and P. ionicus) and showed the presence of at least two more species, one in P. erhardii and the other in P. peloponnesiacus.

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The monophyletic species subgroup of Podarcis tauricus is distributed in the western and southern parts of the Balkans, and includes four species with unresolved and unstudied inter- and intra-specific phylogenetic relationships. Using sequence data from two mitochondrial and three nuclear genes and applying several phylogenetic methods and species delimitation approaches to an extensive dataset, we have reconstructed the phylogeny of the Podarcis wall lizards in the Balkans, and re-investigated the taxonomic status of the P. tauricus species subgroup. Multilocus analyses revealed that the aforementioned subgroup consists of five major clades, with P. melisellensis as its most basal taxon. Monophyly of P. tauricus sensu stricto is not supported, with one of the subspecies (P. t. ionicus) displaying great genetic diversity (hidden diversity or cryptic species). It comprises five, geographically distinct, subclades with genetic distances on the species level. Species delimitation approaches revealed nine species within the P. tauricus species subgroup (P. melisellensis, P. gaigeae, P. milensis, and six in the P. tauricus complex), underlining the necessity of taxonomic re-evaluation. We thus synonymize some previously recognized subspecies in this subgroup, elevate P. t. tauricus and P. g. gaigeae to the species level and suggest a distinct Albanian-Greek clade, provisionally named as the P. ionicus species complex. The latter clade comprises five unconfirmed candidate species that call for comprehensive studies in the future.

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There is growing concern that anthropogenic climate change may particularly affect ectotherm groups such as amphibians and reptiles. Effects of anthropogenic climate change were already observed on different levels, ranging from changes in the phenology of individuals to changes in entire populations, their demography and geographic ranges with losses and range gains. Especially the latter is exacerbated by interactions of climate change with existing risk factors such as the spread of patho- gens and invasive species. In extreme cases, species are threatened by extinction, which is most likely in endemic species occupying restricted ranges. In this review, possible future climate change scenarios as well as previous observations and general expectations of climate change induced changes in phenology, demography and bio- geography of amphibian and reptile species are presented. Individual case studies on climate change induced changes in demography of the common lizard as well as possible range shifts in the alpine newt are highlighted, with applied methods being discussed regarding different elements of uncertainty.

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In recent years, great attention has been paid to many Podarcis species for which the observed intra-specific variability often revealed species complexes still characterized by an unresolved relationship. When compared to other species, P. siculus underwent fewer revisions and the number of species hidden within this taxon may have been, therefore, underestimated. However, recent studies based on genetic and morphological data highlighted a marked differentiation of the populations inhabiting the western Pontine Archipelago. In the present work we used published genetic data (three mitochondrial and three nuclear gene fragments) from 25 Podarcis species to provide a multilocus phylogeny of the genus in order to understand the degree of differentiation of the western Pontine populations. In addition, we analyzed new morphometric traits (scale counts) of 151 specimens from the main islands of the Pontine Archipelago. The phylogenetic analysis revealed five principal Podarcis groups with biogeographic consistency. The genetic distinctiveness of the Podarcis populations of the western Pontine Islands is similar or even more ancient than those observed in numerous other pairs of Podarcis sister species. In the light of these evidences we raise the western Pontine lizards to specific rank; thus they should be referred to as Podarcis latastei.

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Palatal dentition in lizards is incompletely known, especially data on its variability are scarce. We studied variation in the number of pterygoid teeth in three species of Podarcis, a species-rich genus of lacertid lizards: terrestrial, P. siculus and saxicolous, P. erhardii and P. cretensis. In contrast to some previous studies, we found no sexual dimorphism in the number of palatal teeth in any of these species. The number of teeth was not correlated to lizard size. In our sample, P. cretensis on average had more teeth than did P. erhardii but fewer than did P. siculus. In addition, some specimens of P. cretensis and P. siculus showed asymmetry in the number of pterygoid teeth, which may be a result of anthropogenic pressure. The observed variability in the occurrence of palatal dentition illustrates the importance of scoring this character in phylogenetic analyses only on the basis of a sufficient sample.

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Ectotherms thermoregulate mainly by behavioural means. Though they are capable of behaviourally regulating their body temperatures, their natural environments eventually limit the extent of thermoregulatory accuracy. Thermoregulation is also influenced by the presence of competitors and predators as well as by the availability and location of food and retreat sites. In some cases a single species may exhibit different thermoregulatory behaviours in different habitats. Moreover, it is well known that both the thermal environment and the thermoregulatory behaviour of lizards show seasonal variation. Podarcis cretensis is a recently redescribed species of the genus, endemic to the island of Crete and satellite islands where in may be found from sea level to 2000m. The aim of this study was to compare the thermoregulatory strategy of 3 populations of Podarcis cretensis occupying different habitat types, during two seasons: spring and summer 2007. All study sites are in Western Crete, sea level. Ballos is a sandy site in the north coasts of Crete with very low ground coverage by small bushes (phrygana). Elaphonisi is in the south, the ground is a combination of sand and soil and has a high percentage covered by rocks and small bushes. Finally, Lissos gorge is in the south and it is soily with steep edges and high ground coverage by rocks, tall bushes (maquis) and trees. We collected data on the main thermoregulatory parameters (Tb, Te) at the study sites and determined the set-point range (Tset) in a laboratory thermogradient. Thermoregulatory indexes (db, de, E, variance of Tb) were estimated. The efficiency (E) of thermoregulation ranged from 0.47 to 0.83, during spring and from 0.59 to 0.86 during summer, with the population occupying the open (low coverage) phryganic habitat having the lowest value in both seasons (partially thermoconformer during spring). The same population seems to be the less accurate thermoregulator in both seasons, showing that the risk of predation along with the lack of thermal variation within a habitat may be limiting factors to a lizard’s thermoregulation. The effectiveness, the accuracy and the precision of thermoregulation increased during summer in all populations.

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Thermal conditions change dramatically with altitude. Ectothermic animals suffer largely form these alterations to their thermal environments and undergo various adaptations. Thus some lizards show lower body temperatures at high elevations while others adopt behavioural adjustments to compensate for the cooler environment and the climate’s seasonal extremes in these regions. Podarcis cretensis is a recently redescribed species of the genus, endemic to the island of Crete, where it may be found from sea level to 2000m, and satellite islands. The aim of this study was to compare the thermoregulatory strategy of three populations of P. cretensis along an altitudinal gradient (0, 500 and 1000 m). Study sites, all in western Crete, were covered with phrygana and visited during summer 2007. Body temperatures were estimated by taking cloacal temparature from lizards that were captured in the field. In order to assess operative temperatures we used copper models simulating the thermophysical capacities of this species. The set-point range (Tset) was determined in a laboratory thermogradient. Using the values of the aforementioned parameters we estimated the comparative thermoregulatory indexes (db, de, E, variance of Tb). Our results suggest that in all populations lizards are active thermoregulators. The efficiency (E) of thermoregulation ranged from 0.81 to 0.93, with lowland population having the lowest value. Moreover, both accuracy and precision of thermoregulation increased with the altitude.

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P. cretensis is a recently redescribed species of the genus, endemic to the island of Crete and satellite islands. Its distribution on the island is very particular: On Crete it is found only on the ¼ western part of the island and not on the major satellite islands whereas in eastern Crete it is present only on satellite islands. The scope of this work was to study ecological parameters of 6 populations from western Crete, under the light of the recent phylogenetic findings. The 6 populations belong to 3 of the formerly described subspecies. They are distributed in various biotopes: from sandy to rocky, from the north and south part of the island and from sea level to 1000m a.s.l. The ecological parameters we studied are: thermoregulatory strategy (selected, body and operative temperatures), presence of ecto- and endoparasites, population density and aspects of predation pressure. Results are compared to the phylogenetic relationships of the populations as inferred from Cytochrome b sequences.

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Research on the taxonomy of European amphibians and reptiles has increased noticeably over the last few decades, indicating the need for recognition of new species and the cancellation of others. This paper provides a critical review of recent changes and draws up a tentative species list.

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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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In recent years, there have been numerous studies focusing on the systematics of the wall lizards of the genus Podarcis, uncovering several cases of cryptic diversity, such as the cases of the Cretan (southern Aegean) and Pori (islet between Crete and Peloponnisos) wall-lizards that were recently recognized as distinct species (P. cretensis and P. levendis, respectively). In this study, nucleotide sequences from five genes (two mitochondrial – 16S rRNA & cytb and three nuclear – MC1R, pod15b & pod55) were used to infer intra- and inter- phylogenetic relationships of P. cretensis, P. levendis, and P. peloponnesiacus through Bayesian Inference and Maximum Likelihood approaches using P. erhardii as outgroup. Moreover, the boundaries of the putative species were evaluated by employing several species delimitation methods, aiming to ‘determine’ the exact number of species and their phylogenetic status. The phylogenetic analyses revealed that all the examined species are monophyletic. Among them P. levendis, although without statistical support, appear to be more closely related to P. peloponnesiacus. The Cretan species is further subdivided into three major groups of lineages with distinct geographic distributions whereas P. peloponnesiacus into two. The above results combined with the analyses of species delimitation stress the need for a taxonomic reconsideration of the studied taxa both at the species and subspecies level.

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The evolutionary history of taxa with limited overseas dispersal abilities is considered to be majorly infl;uenced by vicariant events constituting them as model organisms for the interpretation of evolutionary processes. An excellent candidate are the wall lizards of the genus Podarcis exhibiting an impressive level of genetic and morphological diversification and harboring several cases of recently discovered cryptic diversity. In this study, we investigated the effect of palaeogeographic events on the wall lizards’ biodiversity patterns in the Aegean (Greece) as well as the evolutionary processes that acted both in space and time. To accomplish that we studied a group of three endemic Podarcis species (i.e., P. cretensis, P. levendis, and P. peloponnesiacus) both at the intra and interspecific levels employing mitochondrial and nuclear DNA sequence data as well as microsatellites. Furthermore, presence information coupled with bioclimatic data (i.e., species distribution modeling, and niche similarity analyses) shed light on the necessary ecological factors for the species’ occurrence. These approaches revealed yet another case of cryptic diversity for this group of lizards, with the existence of two slightly overlapping lineages within P. peloponnesiacus and highly structured populations within P. cretensis. Species diversification occurred during the Pliocene with P. peloponnesiacus divergence into the two lineages dating back to 1.86 Mya. Furthermore, temperature and precipitation related environmental parameters were the most important ones regarding the current distribution of the studied species. Based on the results, we propose a more detailed phylogeographic scenario where both the paleogeography of the area and several environmental parameters have shaped the genetic diversity and the current distribution pattern of this species group.

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Podarcis is a genus of lacertid lizards. It contains over twenty species and represents one of the largest radiations of reptiles in Europe. Podarcis lizards show high molecular diversity but are relatively similar morphologically. Here, I describe cranial osteology of P. muralis, P. siculus, P. hispanicus*, P. melisellensis, P. erhardii, P. peloponnesiacus and P. cretensis. P. erhardii and P. cretensis – until recently regarded as conspecific and considered very similar morphologically – differ in several cranial characters. The studied population of P. cretensis, coming from Elafonisos island, shows some apparently heterochronic traits, such as tripartite occipital condyle, low ascending process of the supraoccipital, open parietal fossa and less well pronounced sexual dimorphism. Heterochrony could also play role in the evolution of P. hispanicus*. This is supported by the absence of median crest of the parietal. Morphometric analyses confirm sexual dimorphism in Podarcis lizards – males have relatively longer and higher skull which results in a higher bite force. This allows them to eat harder prey, enhances their chances in combats and helps maintain a secure grip during copulation.

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Podarcis cretensis is a recently redescribed species of the genus, endemic to the island of Crete and satellite islands. Its distribution on the island is very particular: On Crete it is found only on the ¼ western part of the island and not on the major satellite islands whereas in eastern Crete it is present only on satellite islands. As in other Podarcis species, it exhibits high diversity and great morphological plasticity, which have led to the description of 7 subspecies of the taxon (formerly P. erhardii) in Crete. Here we study the morphological relationships of 6 populations from western Crete under the light of the new phylogenetic relationships. The 6 populations belong to 3 of the formerly described subspecies. They are distributed in various biotopes: from sandy to rocky, from the north and south part of the island and from sea level to 1000m a.s.l. We compared 18 morphological characters (11 metric and 7 pholidotic) of these populations in accordance with indications from the relevant literature. Multivariate analyses techniques were conducted to detect the characters that most differentiate sexes and populations. We compare the results to the formerly recognized subspecies. Moreover we compare the results with the current phylogenetic data as to see if the groupings of populations according to molecular analyses are corroborated by morphological data.

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One of the main concerns in ecology has been identifying and understanding the factors that regulate variation in species distribution. The distribution of Podarcis erhardii (Squamanta: Lacertidae) in Crete is limited to the western part of the islands and some islets in the East. The predicted potential distribution of P. erhardii was modelled by Herkt, who identified that the most important explanatory variable was the multi-temporal Normalized Difference Vegetation Index (NDVI) of the SPOT 4 Vegetation Instrument. The present study’s aim was to identify how much of the variation in the spatial distribution of P. erhardii could be explained by different environmental variables, and if the spatial structure contributed to the observed patterns in highest populated NDVI classes. Seven vegetation types in the selected NDVI classes were classified with TWINSPAN, and their spatial structure was assessed by partitioning the variation in four fractions: pure environmental, environmental and spatial, pure spatial and undetermined using the Borcard’s method. The spatial pattern of the vegetation types assessed by environmental variables and the geographic coordinates was mostly unpredictable. Partitioning the variation of the probability of occurrence of P. erhardii into environmental (vegetation types) and spatial (geographic coordinates) components explained 75.2% of the overall variation. The inclusion of additional environmental variables increased the explained variation to 82.5%, and suggested that the spatial structure of P. erhardii and the environmental variables have a similar spatial structuring: a humidity gradient identified by actual evapotranspiration. This study identified a possible natural barrier related to a climate gradient that may be constraining P. erhardii’s distribution to the Western Crete. Further research should study the effect of this gradient in the locations where P. erhardii was observed.