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TERRA TYPICA. Settlement Levashi in the region with the same name of central Dagestan. DISTRIBUTION. It occurs in the montane Dagestan, southern Chechnya, Ingooshetia and south-east of north Ossetia, from the lower part of the Dar’yal ravine in the west up to Gimrinsky range in the east. The northern border of the distribution area passes in the foothills of the Skalisty range in the upper current of numerous right tributaries of Sunja River. Further on the extreme north-eastern foothills of the frontal ranges of Dagestan it attains the nearest vicinity of Makhachkala city in the east. An isolated population lives also on the southern slope of the Great Caucasus range in the canyon of the river Bol’shaya Liakhvy on the territory of South Ossetia in Georgia. CONSERVATION STATUS. On the most part of the distribution range the number is stable.

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Ilya S. Darevsky co-described 70 taxa (three genera, 46 species, 21 subspecies) in 44 publications belonging to five orders, eight families of amphibians and reptiles during his career in herpetology. Of this number, three taxa are fossil and 57 taxa are currently considered as valid. By the regions where new taxa were discovered Southeast Asia and Western Asia (includes Caucasus and Asia Minor) dominates. The largest number of descriptions was published in the Russian Journal of Herpetology.

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The final part of a series of papers on the lizards of the Caucasus, that have been published in previous years. The paper reports on the life habits, capture and keeping in terraria of several lizards of Soviet Transcaucasia. In these respects the agamid Phrynocephalus helioscopus persi- cus and three species of the lacertid genus Eremias occuring in that area (i. e. strauchi, velox, pleskei) are discussed. Finally a !ist of all lizard species and subspecies actually known to occur in this region is given.

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In Georgia, 16 species of rock lizards of the Genus Darevskia are occuring (D. alpina, D. „armeniaca`, D. brauneri, D. caucasica, D. clarkorum, D. daghestanica, D. „dahli`, D. derjugini, D. mixta, D. nairensis, D. parvula, D. portschinskii, D. praticola, D. rudis, D. „unisexualis` and D. Valentini). Besides short presentations of the single species and hints on their distribution and habitats, also some systematic remarks are given.

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Georgia, its history and the nature are briefly described. This is supplied by a short overview of the country`s herpetological fauna, with particular attention to the especially diverse family of true lizards. At the end, brief description of our common trip to Georgia (May - Juny 2002) is given.

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Many regions of the former USSR still re- ceive little attention from Western visitors, herpetologists not excluded. For the Cau- casus Mountains this is all the more sur- prising since the area forms a zone where northern and Middle Eastern flora and fauna meet, and which is thus of considera- bly zoogeographical interest. Presently we find three larger states in the Caucasus: Georgia, Azerbaijan and Arme- nia. Turkey borders to the southwest, Iran to the southeast, and in the north it is the Russian federation. Various smaller parts claim independence. The Black Sea forms the natural western boundary, the Caspian Sea the eastern one. Herpetologically the Caucasus is historically well-known because of the work of Darev- sky and collaborators on the rock lizards (at the time still in the large genus Lacerta, now in Darevskia) and the discovery of the first case of parthenogenesis in vertebrates (DAREVSKY, 1967; DAREVSKII, 1978; DAREVSKY & KULIKOVA, 1961). Below we will concentrate on the results of our field trip to Georgia during the last two weeks of June 2003. Predictably, because of our common interest in the group, the lacertids will receive the most attention.

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A phylogenetic-comparative approach was used to assess and refine existing secondary structure models for a frequently studied region of the mitochondrial encoded large subunit (16S) rRNA in two large lizard lineages within the Scincomorpha, namely the Scincidae and the Lacertidae. Potential pairings and mutual information were analyzed to identify site interactions present within each lineage and provide consensus secondary structures. Many of the interactions proposed by previous models were supported, but several refinements were possible. The consensus structures allowed a detailed analysis of rRNA sequence evolution. Phylogenetic trees were inferred from Bayesian analyses of all sites, and the topologies used for maximum likelihood estimation of sequence evolution parameters. Assigning gamma-distributed relative rate categories to all interacting sites that were homologous between lineages revealed substantial differences between helices. In both lineages, sites within helix G2 were mostly conserved, while those within helix E18 evolved rapidly. Clear evidence of substantial site-specific rate variation (covarion-like evolution) was also detected, although this was not strongly associated with specific helices. This study, in conjunction with comparable findings on different, higher-level taxa, supports the ubiquitous nature of site-specific rate variation in this gene and justifies the incorporation of covarion models in phylogenetic inference.

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Background. From the genus Darevskia in the territory of Azerbaijan Republic noted 11 species (D. armeniaca, D. caucasica, D. chlorogaster, D. daghestanica, D. derjugini, D. portschinskii, D. praticola, D. raddei, D. rostombekovi, D. rudis, D. valentini). Information on the condition of rock lizards in the republic has not been updated for a long time. The aim of the work was to clarify the data on the distribution and abundance of these species in Azerbaijan.
Materials and methods. The research was carried in the Talysh Mountains (Lenkoran, Lerik and Yardimli districts of Azerbaijan in 2008–2011), in the Great Caucasus (Guba, Gusar, Gabala and Zagatala districts in 2013–2016), in the Minor Caucasus (Dashkesen, Gadabay and Tovuz districts in 2017–2018).
Results. On the basis of own data and analysis of literature sources the data on the distribution and number of rock lizards from the genus Darevskia in Azerbaijan are given. The authors note that the areas of forest lizards of the Talysh (D. chlorogaster and D. praticola hyrcanica) are being reduced and these species need legisla- tive protection. The extinct species for the territory of the Republic should be considered D. derjugini.

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The structure and evolution of a satellite DNA family was examined in lizards from the genus Darevskia(family Lacertidae). Comparison of tandem units of repeated DNA (satDNA), CLsat, in all species from the genus Darevskiahas shown that their variability is largely explained by single-nucleotide substitutions, which form about 50 diagnostic positions underlying classification of the family into three subfamilies. Maximum differences between the subfamilies reached 25%. At this level of tandem unit divergence in the subfamilies, no cross-hybridization between them was observed (at 65°C). The individual variability within one subfamily within the species was on average 5% while the variability between species consensuses within a subfamily was 10%. The presence of highly conserved regions in all monomers and some features of their organization show that satellites of all Darevskia species belong to one satDNA family. The organization of unit sequences of satellites CLsat and Agi160 also detected by us in another lizard genus, Lacerta s. str. was compared. Similarity that was found between these satellites suggests their relatedness and common origin. A possible pathway of evolution of these two satDNA families is proposed. The distribution and content of CLsat repeat subfamilies in all species of the genus was examined by Southern hybridization. Seven species had mainly CLsatI (83 to 96%); three species, approximately equal amounts of CLsatI and CLsatIII (the admixture of CLsatII was 2–5%); and five species, a combination of all three subfamilies in highly varying proportions. Based on these results as well as on zoogeographic views on the taxonomy and phylogeny of the Darevskia species, hypotheses on the evolution of molecular-genetic relationships within this genus are advanced.

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The genetic relatedness of several bisexual and of four unisexual Lacerta saxicola complexlizards was studied, using monomer sequences of the complex-specific CLsat tandem repeats and anonymous RAPD markers. Genomes of parthenospecies were shown to include different satellite monomers. The structure of each such monomer is specific for a certain pair of bisexual species. This fact might be interpreted in favor of co-dominant inheritance of these markers in bisexual species hybridogenesis. This idea is supported by the results obtained with RAPD markers; i.e., unisexual species genomes include only the loci characteristic of certain bisexual species. At the same time, in neither case parthenospecies possess specific, autoapomorphic loci that were not present in this or that bisexual species.

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A new subspecies of Lacerta caucasica (s. str.), L. c. vedenica from the northern slope of the Andiiskii Ridge (SE Chechenia) is described. This population appears to be geographically isolated from the main range of L. caucasica, but contacts the northern limits of the range of a closely related species, L. daghestanica. It differs from the other populations of L. caucasica as well as from the related species, L. daghestanica and L. alpina by a very low number of superciliary granules and superciliary scales as well as by the lack of greenish paints in the dorsal coloration.

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The paper provides information on the current status of the type specimens of Darevskia (caucasica) complex as they were in August 2014. In order to stabilize nomenclature of this complex, the lectotype of Lacerta saxicola daghestanica Darevsky, 1967 is designated. The description of external morphology of paralektotype of a L. s. daghestanica, lektotype and paralektotype of Lacerta caucasica Méhely, 1909 is given. History of description of these taxa is discussed.

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1. Sexual dimorphism and geographical variability in signs of external morphology are revealed in the species of the studied complexes of rock lizards. The most important for their diagnosis are the features of folidosis of the head. Interspecific and intraspecific differences in morphometric features, color and pattern of the body were detected. 2. In the phylogenetic analysis, the Darevskia (caucasica) samples were divided into the group of the northern slope of the Central Caucasus (D. caucasica), the East Caucasus (D. daghestanica), the Western Caucasus (D. alpina), the northern slope of the Central and Western Caucasus (D. alpina ). Reliable identification and significant genetic differences of D. caucasica and D. daghestanica samples favor their attribution to different species. Within D. alpina two groups with high genetic differences (distances) were identified. Inside Darevskia (saxicola) two lines are described, one of which is connected with the Crimea and the Western Caucasus (D. lindholmi-D. Brauneri), and the second - with the North and West Caucasus (D. saxicola-D. Szczerbaki). 3. As a result of the nomenclatural revision, the lectotype Lacerta praticola pontica, L. saxicola brauneri, L. saxicola daghestanica, L. saxicola lindholmi, and the neotype L. saxicola; Specific locations, years and authors of the description of a number of taxa have been refined. 4. It has been established that the studied supernumerary complexes include the following valid taxa: Darevskia (praticola) - D. pontica pontica, D. pontica hungarica, D. praticola praticola, D. praticola hyrcanica, D. praticola loriensis; Darevskia (caucasica) - D. alpina, D. caucasica caucasica, D. caucasica vedenica, D. daghestanica; Darevskia (saxicola) - D. brauneri brauneri, D. brauneri myusserica, D. saxicola, D. szczerbaki, D. lindholmi. Lacerta saxicola darevskii is regarded as a minor synonym for Lacerta saxicola brauneri. 5. For the first time accurate inventories of findings (1,443 locations) and GIS maps of species arealways were compiled, reliably characterizing the features of their distribution; The structure of areals, the current trends of their changes and the factors influencing the distribution of rock lizards are revealed. It is recommended to carry out conservation measures of international and national level in order to preserve the populations of D. alpina, D. brauneri myusserica and D. szczerbaki, especially in typical territories. 6. The first and only reliable paleontological find of Darevskia sp. - Darevskia sf. brauneri from the Pleistocene site, the caves of Mezmaiskaya. A hypothesis is proposed for the formation of species of complexes, according to which the isolation of their common ancestor from a hypothetical form it is logical to associate with the Miocene and Pliocene boundaries, or with the Cimmerian century of the Pliocene, 153 and the radiation of modern species - with the Akchagylian age, corresponding to the Piacenza and Gelazian tiers. The parallel formation of several Darevskia (praticola) and Darevskia (caucasica) lines around the Greater Caucasus is assumed in the early Pliocene. At the end of the Pontian age, the primary area of ​​the ancestor of the modern forms of Darevskia (saxicola) and the subsequent formation in the Mediterranean landscapes of the Black Sea coast, along the surviving cliff, D. szczerbaki, and the cuestas of the North Caucasus - D. saxicola, could have occurred at the periphery of the Caucasian peninsula.

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New data on the distribution of four species of lizards (Darevskia brauneri, D. daghestanica, Lacerta agilis ioriensis, L. strigata) in the Caucasus are presented.

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The range of superspecific complex of rock lizards Darevskia (caucasica) (D. alpina, D. c. caucasica, D. c. vedeni- ca, D. daghestanica) includes the Main Caucasian ridge and its spurs on the southern and northern macroslopes within heights from 500 m to 3200 m above sea level. A fragment of the mitochondrial cytochrome b gene (1096 bp) was analyzed in 48 specimens of these lizards. Specimens were collected in 23 localities. We have found 39 unique haplotypes. The minimum genetic diversity was found in D. c. vedenica, maximum in D. c. caucasica. All taxa of the complex, except for D. c. vedenica, demonstrate genetic heterogeneity. Four clades can be distinguished on the dendrogram of phylogenetic relationships. They correspond to D. alpina, D. c. caucasica, D. c. vedenica, D. dagh- estanica. D. c. caucasica forms two distinct haplogroups. On the phylogenetic tree, the sample of D. c. vedenica formed an independent clade close to D. c. caucasica. The Darevskia (caucasica) complex is polyphyletic accord- ing to the analysis of the mitochondrial marker. Nucleotide sequences of D. alpina formed a single clade with Darevskia (saxicola) complex representatives and combined with the sequences of D. brauneri into subclade. On the example of the population of D. daghestanica, found in a forest biotope without rocky outcrops and genetically not differing from individuals from the adjacent territory, the ability of rocky lizards to master biotopes unusual for them in a short period of time was demonstrated. This example demonstrates the ability of rock lizards to adapt to unusual biotopes in a short period of time. Genetic distance between D. c. vedenica and D. c. caucasica is com- parable to the distance between D. c. caucasica and D. daghestanica. We assume the existence of an independent form of D. caucasica ssp. inhabiting South Ossetia and adjacent territories.

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Five new regional records of the rock lizards in Caucasus are described. The distribution of Darevskia alpina (Darevsky, 1967) on the northern slope of Mount Elbrus has been detailed: the species was found in the Emmanuel glade and in the gorge of the Kyzylkol River. The easternmost record of D. alpina is located in the upper stream of the Cherek Bezengi River in Kabardino-Balkaria. Darevskia caucasica vedenica (Darevsky et Roitberg, 1999) was first found on the territory of Dagestan in the area of the lake Kezenoyam and on the watershed of the Okholitlau and Khulhulau rivers. The existence of an isolated population of D. daghestanica (Darevsky, 1967) in the gorge of the Bolshaya Liakhvi River was confirmed, which is located in South Ossetia, on the southwestern border of the species range. When studying the collections of the Zoological Institute of the Russian Academy of Sciences, three specimens of D. dahli (Darevsky, 1957) were found from the village Alapars of the Kotayk region of Armenia collected in 1880. This locality is the southernmost and, moreover, the only record of the species in the Armenian volcanic highlands.

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e results of molecular genetic analysis of phylogenetic relationships in Darevskia (caucasica) on the basis of COI sequences variability is presented. Two main lineages are detected: the Central and Eastern Caucasian (clades A–B — D. caucasica-D. daghestanica), and Central and Western Caucasian (clades C–D — D. alpina). A DNA-barcoding tool can be successfully used for species identi cation of D. alpina, D. caucasica and D. daghestanica.

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From the publisher: Before you a unique atlas-determinant. For the first time in one edition descriptions of all species of amphibians and reptiles living on the territory of Russia are presented, illustrated with beautiful color photographs. The book is written by E.A. Dunaev and V.F. Orlova, the famous Russian herpetologists, researchers of the Zoological Museum of Moscow State University named after MV Lomonosov. Lomonosov. A simple and accessible form of presentation, detailed descriptions of the external appearance, lifestyle and behavior, photographs reflecting all variants of the variability of these animals, will help the curious reader to become more familiar with turtles, snakes, lizards, frogs and other representatives of the herpetofauna. And special keys will allow you to determine who you met on a country walk, in a city park, at a dacha or while traveling to different corners of our country. The book is of great interest not only for nature lovers, but also for specialists in herpetology and students of biological faculties of universities. It lists the amphibians and reptiles of the native fauna, reflects the latest changes in the taxonomy of these groups, lists species included in the Red Book of Russia and regional Red Books, lists reference and scientific publications on reptiles and amphibians of Russian fauna.

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Considering all costs associated to sex, sexual reproduction could be expected to be rare. However, we find sexual reproduction to be pervasive in nature, and only a reduced number of taxa are completely asexual. In fact, the variety of sex reproductive systems, mating techniques and traits, reveals that the organisms’ reproduction has been an expressive target of selection and adaptation throughout evolution. Sex is selected because it facilitates adaptation in complex and changing environments (Weismann, 1889), and this has been already shown empirically in several models. However, studies and theories developed concerning the paradox of sex will not be able to clarify the current distribution and abundance of asexual lineages in nature. The understanding of rates of origin and extinction of asexual lineages, together with the putative differential evolution rates in organisms with sexual or asexual reproduction, should be considered in the main “origin of sex” question. The model used here, the genus Darevskia, is the first true parthenogenetic vertebrate described. It is a highly speciose genus, currently including 27 species, of which seven are parthenogenetic and of hybrid origin. Only a few of the sexual species contributed for the hybridization events which originated the parthenogens clonal lineages, and these were directional: the maternal species were always Darevskia raddei or D. mixta, and the paternal always D. valentini or D. portshinskii. Using a set of microsatellite and mtDNA markers, we first start to study the role of hybridization in the origin of vertebrate parthenogens, the extent of gene flow with sexual relatives and the relation between hybridization, asexuality and polyploidy, in the context of the main theories of asexual evolution proposed to date. We focus on the D. unisexualis, D. uzzelli and D. armeniaca parthenogens and polyploid backcrosses found in sympatric locations between the parthenogens and its sexual parentals. We find that only specific parental pairs are responsible for the origin of vertebrate parthenogenesis, regardless of their phylogenetic distance. Despite the recurrent hybridization presently reported in Darevskia, asexuality originated multiple times but only in a single temporal event the past. Parthenogenetic females are capable of backcrossing with sexual males, but can only produce polyploid individuals with reduced fertility that do not contribute for gene flow between parthenogens and sexuals. The sexual reproduction machinery can be lost with time in the parthenogenetic hybrids, which are most likely the result of a post-zygotic reproductive barrier to gene flow in the speciation continuum of Darevskia sexual species. In order to reconstruct the phylogenetic inference of this group, a set of capture sequence probes were designed from a transcriptome de novo assembly. Phylogenetic inference reconstruction has been extensively used to ask several evolutionary biology questions. However, despite the exponential use of high-throughput sequencing technologies and its promising applications in phylogenetics, next generation sequencing (NGS) techniques are still far from being as widely used in this field as in other areas of evolutionary genetics. The workflow developed in this thesis has proved to be not only cost-effective, but also to produce a very high number of cross genome phylogenetically informative markers in this non-model species. Finally, taking advantage of the hundreds of cross genome markers developed, a species tree was constructed and within genus relationships evaluated. Introgression tests showed a widespread pattern of gene flow across the genus, not only recent between recently diverged clades, but also both recent and ancient gene flow between early diverging Darevskia clades. Several evidences of hybridization with gene flow between diverging clades have been found in other systems. However, such widespread patterns where introgression has happened between all major clades, and in a very high number of species pairs, are not frequently found. It is also found that gene flow is completely absent between parthenogens sexual parental pairs. In groups with sexual-parthenogenetic reproducing species, pre- or post-zygotic reproductive barriers could be more difficult to attain and hybrid asexuality can, thus, effectively create reproductive barriers between diverging sexual taxa, that were likely faced with recurrent secondary contact. The work presented in this thesis shows that only a few sexual species pairs were responsible for the origin of the parthenogens, that some species acted always as the maternal species and others always as the paternal, that the phylogenetic distances between each pair are included in a wide range interval, and that introgression is found widespread across the genus but absent between the parental pairs. Regardless of the reproduction type, this study also shows the relevance and depth of hybridization during divergence. As has been shown intensively, gene flow is common during speciation and clades divergence. However, it would be interesting to analyse other groups together and test if deep branch gene flow is found only in some exclusive groups (such as sexual-asexual genera) or if it is something more widespread. This work presented here moves Darevskia towards providing a model that can be used to understand the origin of asexuality in vertebrates. Here the basis for future studies about sex and asexuality is provided, so that a focus on the differential evolution rates genomes of both reproduction mode can be analysed.

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The genetic diversity of 34 loci was surveyed from among five populations of the supposed conspecific taxa Lacerta c. caucasica, L. c. alpina, and L. c. daghestanica. Twelve loci exhibited variation. Fixed or nearly fixed allelic differences between L. c. caucasica and L. c. daghestanica were found at two loci, mannose-6-phosphate isomerase-A and creatine kinase-C. These two taxa differed from L. c. alpina at eight loci. Nei`s (1978) genetic distance values among populations of L. c. daghestanica ranged from 0.000 - 0.029, between L. c. caucasica and L. c. daghestanica from 0.076 - 0.087 and between L. c. alpina and the other taxa from 0.472 - 0.501. Fixed allelic differences and consistent morphological character states support the recognition of these three taxa as separate species. Therefore, we recommend use of the names L. alpina, L. caucasica, and L. daghestanica for these taxa.

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A maximum parsimony phylogeny of 14 Caucasian species of rock lizards, genus Ijicerta, subgenus Archaeolacerta, was constructed from mitochondrial cytochrome b and ATPase 6 partial gene sequences. Congruence analyses were carried out between the two genes. A synthesis of the data sets reveals three well supported monophyletic groups: (1) the caucasica group including (Lacerta derjugini ((Lalpina, L. clarkorum) (L. caucasica, L. daghestanica))); (2) the rudis group including (L. parvula (L. portschinskii (L. vakntini, L. rudis))); and (3) the saxicola group including (L. mixta (L. nairensis (L. saxicola, L. raddeijj). Despite the diagnosis of three groups, the placement of L. praticola as a basal taxon is uncertain, as are the relationships among the three groups. The mitochondrial DNA sequence data suggested prior hybridization between L. mixta and L. alpina and possibly between L. saxicola and L. nairensis. Lacerta raddei was resolved as a paraphyletic species on the mtDNA tree; this may result from either hybridization or random gene sorting.

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The paper presents the results of studying the reproductive biology of Darevskia da- ghestanica in the valleys of Khzanor and Kitlyarta rivers (Tsunta district, Republic of Dage- stan, Republic of Dagestan). Adult females were caught in the II–III decades of May 2021. In the following, the animals were kept singly in a laboratory. Lizards laid eggs from the third decade of May to the second decade of June. The body length of breeding females was 43.95– 56.20 mm. Each clutch contained from 1 to 5 eggs with a length of 6.05‒14.47 mm, a width of 4.28‒7.30 mm and a weight of 0.10‒0.40 g. Incubation in artificial conditions lasted 36–51 days. The body length of young lizards emerging from eggs was 20.24‒27.52 mm, and the mass was 0.20‒0.42 g. The length of eggs in a clutch negatively correlated with the fertility of females, and also statistically significantly differed in clutches with different number of eggs. The authors conclude that D. daghestanica is similar to other representatives of the Darevskia (caucasica) complex, as well as to lizards from the Darevskia (praticola) complex in terms of reproductive phenology, size of breeding animals, fertility and the size of offspring.

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Anatomical-morphological features of the postcranial skeleton of nine taxa of the rock lizards of the genus Darevskia Arribas, 1999 belonging to the Darevskia (caucasica) and Darevskia (saxicola) complexes were studied for the first time on representative samples. Specimens with the rib formula 3+1 were found in both complexes (previously, only two variants were known for the genus Darevskia 3+2 and 3+3). Differences between supraspe- cific groups and their members were described with the use of type specimens or topotypes of each taxon. The studied complexes are differentiated by the range of variability of presacral vertebrae (in the D. (caucasica) their minimum number is 26, in the D. (saxicola) – 27), the number of the posterior presacral vertebrae with ribs (the average value of this trait in the D. (caucasica) is less than 6, in D. (saxicola) – more than 6). B-type of the tail vertebrae in 5 times more common in the D. (saxicola) than in the D. (caucasica). In turn, the latter group is cha- racterized by a larger share of individuals with ossified ribs at the third cervical vertebra and a greater variability of the sternal-xiphisternal costal (rib) formula. Skeletal morphology of D. alpina indicates its greater similarity with representatives of the D. (caucasica) complex. A certain originality of D. c. vedenica was recorded. The study of D. saxicola specimens from the zone of sympatry with D. c. caucasica (Chegem Gorge) did not reveal their simi- larity with the latter, except for the presence of two variants of the sternal-xiphisternal formula. Cryptic forms within D. lindholmi differ at least in two traits: the minimum number of posterior presacral vertebrae with short ribs and the presence of individuals with caudal vertebrae of B-type.

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The study of genome size variation in cells of vertebrates using the DNA flow cytometry makes it possible to precisely determine polyploid individuals, which is extremely important when studying the processes of reticulate speciation. In addition, in many groups of vertebrates, closely related species often differ in the nuclear DNA content. Therefore, the purpose of our study was to explore the variability of genome size and ploidy in populations of 29 species and subspecies of mountain lizards of the genus Darevskia, as well as their hybrids. As a result of the study, the range of variability in individuals of different ploidy (91% of diploid and 9% of triploid individuals) was established not to overlap. Among diploid species, no correlation was found between the nuclear DNA content and phylogenetic relationships, geographic coordinates, altitude, average annual temperatures and precipitation. Representatives of all studied species complexes (with the exception of D. adjarica) had approximately the same limits of variability. Two species (D. derjugini and D. saxicola) show significant intraspecific variability. Comparisons of the genome size of parthenogenetic and bisexual species generally revealed no noticeable differences between them. Studies of triploid hybrids have shown that their genome size as a whole roughly corresponds to the sum of the average size of the diploid genome of the maternal parthenogenetic species and the haploid genome of the paternal species. The variability of genome sizes within samples of triploid hybrids was on average slightly higher than in most parthenogenetic species, but some lower than in bisexual species. The paper discusses peculiarities of reticulate speciation in this group of animals.

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Darevskia caucasica vedenica is a most poorly studied taxon of the genus Darevskia. Data and some considerations confirming the validity of D. c. vedenica are given. A new record of D. c. vedenica from the upper stream of the Fortanga River, 5 – 7 km east from the Verkhniy Alkun settlement (Ingushetia) in a mountain forest at 700 – 1000 m a.s.l. is reported. The contours of the proposed geographic range of D. c. vedenica coincide with the border of the most humid (above 800 mm per year) and cool (average annual isotherms + 4– +6 °С) zones in an altitude range of 700 – 2000 m. a.s.l. A probable scenario of the formation of D. c. vedenica is discussed.

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The paper describes the history of biogeographic views on the herpetofauna of both Dagestan and the Caucasus as a whole. The species are grouped into eight zoogeographic groups on the basis of our de- tailed chorological analysis. Mesophilous and xerophilous refuges of the Dagestan herpetofauna are de- scribed. Our herpeto-geographical subdivision of the territory is given. The territory of Dagestan is lo- cated in the Palaearctic subkingdom of Holarctic kingdom and divided between two areas, namely, the Turanian and Mediterranean ones. The boundary between the regions is the junction of the northern foot- hills and plains of the Eastern Caucasus. A possible reconstruction of the regional herpetofauna genesis is considered.

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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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The phylogeny of 12 species of Caucasian rock lizards and ground lizards, genus Lacerta, subgenus Archacolacerta, was determined from allozyme data. Three additional species of Lacerta Sorlned the outgroup. Of the 35 loci resolved, 20 were phylogenetically informative. Permutation tail probabilities calculated using Hennig86 and RandomCladistics and g, statistics obtained in PAUP revealed significant pattern in the data. Our analysis resolved 12 most parsimonious trees; among which were three well-supported monophyletic groups: I) (Lacerta alpina, L. caucasica, L. daglzestanica) [the L. caucasica group]; 2) (L. mixta. L. saxicola. L. raddei-nairensis) [the L. saxicola group]; and 3) (L. parvlila, L. portschinskii (L. valentini, L. rudis)) [the L. ruciis group]. The second and third groups formed a clade. The ground lizards L. praticola and L. derj~cginwi ere resolved as ingroup members. but their placement in the globally most parsimonious trees was ambiguous. A preferred tree was chosen by alternately pruning L. praticola and L. devugini from the tree. In doing so, L. praticola was resolved as the sister taxon of the L. calccasica group; and L, derjligini was resolved as the sister taxon of the clade containing the L. snxicola and L. rrldis groups. Our results are somewhat congruent with the morphology-based phylogeny of Darevsky (1967).

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About 170 specimens of L. c. caucasica and L. c. daghestanica from two localities where they had been found to coexist sympatrically, were studied for color pattern and 7 meristic scale characters. In Khorachoi (south-eastern Chechnya) the specimens of the two forms differ clearly by their dorsal pattern and form two sharply discrete classes along PCI in the principal component analyses of scalation; a distinct hiatus between the two taxa was revealed for the superciliary granulae number. In Khvarshi (western Daghestan), the morphological separation between the two forms is somewhat weaker than in Khorachoi for both scalation and color pattern. Some reproductive isolation between L. c. caucasica and L. c. daghestanica in the studied sections of their contact zone is proposed.

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Based on 270 specimens from 7 populations of Lacerta alpina, L. caucasica, L. daghestanica and L. praticola, morphological relationships between the four species were studied for 7 meristic characters and 5 morphometric characters, using canonical variate analysis. In both scalation and morphometry, the contours and centroids of the studied populations form a trend: L. praticola – L. caucasica – L. daghestanica, which represents the main direction of phenetic differentiation between the studied taxa (60–80% of the total among-group variation). Possible factors, determining this trend, as well as the problem of evolutionary polarity in the morphological series of the three species are discussed.

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Five sympatric populations of Lacerta caucasica (s. st.) and L. daghestanica from the eastern North Caucasus were examined for color pattern (qualitatively) and seven scalation and five morphometric characters by using multivariate and univariate biometrical procedures. In all five localities, daghestanica form differs from caucasica one in having more scales in different meristic rows (scales around midbody, ventrals, femoral pores, superciliary granules, temporals, but not circumanalia), relatively long, narrow and flattened head and longer hindlegs. The degree of phenetic separation between these: two sympatric forms was found to vary from a distinct specific level in the South-East of Chechen Republic to a slight intergradation in southwestern Daghestan. These differences in the level of morphological separation manifest themselves both in scalation and morphomerty, but the latter set of characteristic was less discriminative. Taking into account some features of geographic relations between daghestanica and caucasica forms, it was suggested that different portions of their contact zone had fixed different stages of evolutionary divergence.

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Die Echsenfauna Dagestans (südöstlicher Nordkaukasus, Russland) umfaßt 17 Arten, welche neun Gattungen in fünf Familien angehören (Gekkonidae - l, Agamidae - 4, Anguidae - 2, Scincidae – l und Lacertidae - 9 Arten). Für jede Art wurden detaillierte Verbreitungskarten mit Katastern in Dagestan (50 300 km2) erstellt. Einige Angaben zu den Habitaten, zur Häufigkeit sowie über die lokale Arealdynamik werden ebenfalls mitgeteilt.

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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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Phenotypic evolution can cause either divergent or convergent phenotypic patterns. Even adaptation to the same environment may result in divergence of some elements of phenotype, whereas for other morphological traits it could cause phenotypic convergence. We hypothesize that at least some phenotypic characters diverge monotonically, hence they evolve irreversibly even in very closely related species, and this happens in spite of multiple convergent adaptive patterns. We studied the evolution of phenotype in 13 closely related Caucasian rock lizards (Darevskia), whose phylogenetic relationships are well known. We used head shape and the outlines of three important scales, using geometric morphometrics. We studied the association of the overall head shape, individual principal components of head shape and scale outlines with four predictors: phylogeny, habitat, sex and size. The overall head shape was not correlated with any of these predictors, whereas some principal components were correlated with habitat or phylogeny. Habitat type explained the highest fraction of variation in head shape and anal scale area. The relatedness inferred from the components of phenotype not correlated with habitat was congruent with the phylogenetic tree inferred from molecular data. Although adaptation to local environments may obscure the phylogenetic signal present in phenotype, there are components of phenotype whose evolution is irreversible