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TERRA TYPICA. Town Abastumani in south-western Georgia. DISTRIBUTION. Endemic of Georgia. The recent distribution range forms some more or less extensive isolates mainly situated on the slopes of the Meskhetsky range within Ajaria and western Georgia up to Borzhomi ravine in the valley of Kura River and north-western slopes of Trialetsky range in the east. Isolated populations live on the southern slopes of Lechkhumsky and Rachinsky ranges in the foothills of Great Caucasus, where this lizard is known from the vicinity of the towns Kutaisi, Tkvibuli and the health-resort Labarde. Its distribution in the foothills of the Great Caucasus Range is still not sufficiently studied. CONSERVATION STATUS. The number in the most of known populations is rather high and stable.

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Morphological diversity at 20 pholidotic and 16 meristic characters were studied on three parthenogenetic species Darevskia unisexualis (Darevsky, 1966) D. uzzelli (Darevsky & Danielyan, 1977) and D. sapphirina (Schmidtler, Eiselt & Darevsky, 1994) from Turkey which originated from interspecific hybridization of same parental species D. raddei (Boettger, 1892) and D. valentini (Boettger, 1892) and compared with parthenogenetic species D. armeniaca (Mehely, 1909) which originated from hybridization of D. mixta (Mehely, 1909) and D. valentini (Boettger, 1892) (Murphy et al, 2000, Fu et al, 2000). D. armeniaca significantly differ (ANOVA, Tukey HSD test; p < 0.05) from D. unisexualis and D. sapphirina by 11 pholidotic characters, as well as from D. uzzelli by 9 variables. D. unisexualis has shown significant differences by 8 pholidotic variables from D. sapphrina. Only two pholidotic characters distinguish D. uzzelli from D. sapphirina and D. unisexualis. In addition to meristic characters D. sapphirinia has shown significant less length and height of head as well as length of legs than D. armeniaca, D. unisexualis and D. uzzelli. The average means of snout-vent length of D. sapphirina were less in each age group in comparing with other species. The measurements of bone thickness have revealed the significant high level (p<0.001) of endosteal resorption in femur bones of D. sapphirina removing the first growth layers which usually present in bones of the most Darevskia species. The oldest lizards in our specimens were aged 6 years in D. uzzelli and D. sapphirina and 7 years D. unisexualis and D. armeniaca.

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Head shape plays a crucial role in ecological and evolutionary processes in lizards, and scientists have studied head shape using traditional and 3D geometric morphometrics. Lizards are classic subjects for ecological studies because closely related and ecologically similar species coexist. Sympatric species tend to show higher levels of morphological divergence compared to allopatric species. In this study, we focus on two parthenogenetic Darevskia species (Darevskia dahli and Darevskia armeniaca) that share a maternal species, Darevskia mixta, but have different paternal species (Darevskia portschinskii and Darevskia valentini). We aim to assess the relative importance of morphologically inheritable traits and environmental conditions on head shape in these parthenogenetic species. Specifically, we aim to determine whether local adaptations or intermediate phenotypes between parental species drive head shape variation in parthenogens. To accomplish this, we analyze the head shapes of samples from both parthenogens, their paternal species, and their common maternal species from 3 sites in Georgia. Our study shows that certain aspects of head shape are associated with body size and habitat climate, with high mountain species exhibiting larger and deeper heads with stronger jaws regardless of breeding mode. In addition, both parthenogens exhibit narrower and more elongated jaw areas, flatter mandibles, and thus weaker jaws compared to females of their maternal and paternal species.

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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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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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The purpose of this work, under Articles 23.9.1.2, 23.9.2, and 24.2 of the International Code of Zoological Nomenclature, is to conserve the priority of the specific name Lacerta mixta Méhely, 1909. This name is threatened by the never-used-as-valid name Lacerta composita Méhely, 1909. It is proposed that Lacerta mixta, Méhely, 1909 is given precedence as a nomen protectum over Lacerta composita Méhely, 1909, which will be considered as a nomen oblitum.

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The information is given on finding of males, having characters similar with Darevskia mixta (settled in 1968) and with D. armeniaca in the structure of the mixed experimental population of rocky lizards D. armeniaca and D.dahli. Data about distribution of the above mentioned species in the territory populated by them, characters of external morphology and others are cited. The possible reasons of not planned occurrence `D.dahli` in the population of D. armeniacа, including by hybridization are considered.

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A specially optimized restriction analysis of highly repetitive DNA elements, called DNA taxonprint, was applied for phylogenetic study of primates and lizards. It was shown that electrophoretic bands of DNA repeats revealed by the taxonprint technique have valuable properties for molecular systematics. Approximately half of taxonprint bands (TB) are invariable and do not disappear from the genomes during evolution or change spontaneously. Presumably these invariable bands are restriction fragments of dispersed DNA repeats. Another group represents variable taxonprint bands that differ even between closely related species. These variable bands are probably represented by tandem DNA repeats and could be used as species-specific markers. It was shown that taxonprint bands are independent characters since the appearance of a new taxonprint band does not change the previous band pattern. Phylogenetic reconstruction carried out on taxonprint data demonstrated that this approach could be of general utility for molecular systematics and species identification.

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Presently, the lacertid fauna of Turkey consists of 67 species and subspecies. Since 1990 one species has been recorded as new for Turkey (Acanthodactylus schreiberi), and four species (Darevskia dryada, D. `bendimahiensis`, D. `sapphirina`, Lacerta cyanisparsa) and two subspecies (D. valentini spitzenbergerae, D. raddei vanensis) were newly described. Contrastingly, the formerly listed D. r. raddei does not occur in Turkey. Furthermore it is proposed to reject Parvilacerta parva from the fauna of the European part of Turkey until its presence there has been confirmed, and to reject Darevskia mixta from the Turkish herpetofauna until the record has been confirmed or the material has been re-examined. In addition, an overview on taxonomical changes and new distributional data regarding Turkish lacertids since 1990 is given. Finally, a checklist of all taxa currently known from Turkey is presented.

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Hybridization is a common evolutionary process with multiple possible outcomes. In vertebrates, interspecific hybridization has repeatedly generated parthenogenetic hybrid species. However, it is unknown whether the generation of parthenogenetic hybrids is a rare outcome of frequent hybridization between sexual species within a genus or the typical outcome of rare hybridization events. Darevskia is a genus of rock lizards with both hybrid parthenogenetic and sexual species. Using capture sequencing, we estimate phylogenetic relationships and gene flow among the sexual species, to determine how introgressive hybridization relates to the origins of parthenogenetic hybrids. We find evidence for widespread hybridization with gene flow, both between recently diverged species and deep branches. Surprisingly, we find no signal of gene flow between parental species of the parthenogenetic hybrids, suggesting that the parental pairs were either reproductively or geographically isolated early in their divergence. The generation of parthenogenetic hybrids in Darevskia is, then, a rare outcome of the total occurrence of hybridization within the genus, but the typical outcome when specific species pairs hybridize. Our results question the conventional view that parthenogenetic lineages are generated by hybridization in a window of divergence. Instead,

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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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Obligate parthenogenesis is found in only 0.1% of the vertebrate species, is thought to be relatively short lived and is typically of hybrid origin. However, neither the evolutionary persistence of asexuality in vertebrates, nor the conditions that allow the generation of new parthenogenetic lineages are currently well understood. It has been proposed that vertebrate parthenogenetic lineages arise from hybridisation between two divergent taxa within a specific range of phylogenetic distances (the ‘Balance Hypothesis’). Moreover, parthenogenetic species often maintain a certain level of hybridisation with their closest sexual relatives, potentially generating new polyploid hybrid lineages. Here we address the role of hybridisation in the origin and evolutionary lifespan of vertebrate parthenogens. We use a set of microsatellite markers to characterise the origins of parthenogens in the lizard genus Darevskia, to study the distinctiveness of sexual and asexual taxa currently in sympatry, and to analyse the evolutionary consequences of interspecific hybridisation between asexual females and sexual males. We find that parthenogens result from multiple past hybridisation events between species from specific lineages over a range of phylogenetic distances. This suggests that the Balance Hypothesis needs to allow for lineage-specific effects, as envisaged in the Phylogenetic Constraint Hypothesis. Our results show recurrent backcrossing between sexual and parthenogenic Darevskia but neither gene flow nor formation of new asexual lineages. We suggest that, along with their demographic advantage, parthenogens gain additional leverage to outcompete sexuals in nature when the retention of sexual reproductive machinery allows backcrossing with their sexual ancestors.

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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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Little mtDNA variation was observed among populations of the bisexual Caucasian rock lizard Lacerta mixta and unisexual L. dahli and L. armeniaca. Three haplotypes were detected in L. mixta and the maximum pairwise difference among the samples was 0.67%. No intra- and interspecific variation was found among populations of either L. armeniaca or L. dahli. Moreover, both unisexual species were identical to one of the three haplotypes of L. mixta. The limited variation in L. mixta is likely the result of bottleneck effect, although the small sample size may also be responsible. The lack of variation in the unisexuals was attributed to the restricted variation among the maternal parents, limited involvement of females in the hybridization, and recent origin.

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The genus Darevskia comprises over 20 species of small-bodied lizards, mainly occurring in the Caucasus Mountain Region. They show differences in body size, scalation and coloration, however, fully diagnostic characters that could separate the species with a high confidence level are still lacking. The early phylogenetic hypothesis of this group was based on ‘traditional’ analysis of morphology, based on multiple body and head measurements and scalation traits. Later, a molecular phylogeny of the genus rejected some of the proposed topology based on morphological traits. In this paper, we used quantitative morphological data (outline-based shape data) to test phylogenetic similarities, as proposed by these earlier hypotheses. We analyzed the pileus shape and the anal area of more than 200 individuals, representing six species of Darevskia, using outline based elliptic Fourier analysis. The analysis did confirm a clustering of the individuals and species (using UPGMA) from the same mitochondrial DNA clade. Hence, the phylogenetic affinity of the major clades in Darevskia could be identified using both molecular methods and outline analysis, whereas a traditional quantitative morphological analysis could not.

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The Caucasian rock lizard Darevskia mixta was sampled and studied from throughout its range, using mitochondrial cytochrome b sequences and scalation. The populations of the Greater and the Lesser Caucasus are reciprocally monophyletic matrilineally, and the respective lineages have been separated since the mid-Pleistocene. The lizards from the Greater Caucasus commonly have an unpaired preanal scale, whereas the lizards from the Lesser Caucasus have an additional scale behind the central temporal and subdivided interparietal scale more commonly than those from the Greater Caucasus. The Lesser Caucasus populations are further subdivided into two geographically distinct matrilineages, and are more diverse genetically and morphologically than the Greater Caucasus populations. The central part of the Lesser Caucasus is suggested to be the ancestral area for the entire D. mixta lineage. Successive Pleistocene periods of glaciation appear to be responsible both for the isolation of D. mixta from its common relatives, and for subdivision within D. mixta. Presence of D. mixta in NE Turkey is challenged.

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Satellite DNA repeats were studied in Caucasian populations of 18 rock lizard species of the genus Darevskia. Four subfamilies (Caucasian Lacerta satellites (CLsat)I–IV) were identified, which shared 70%–75% sequence similarity. The distribution of CLsat subfamilies among the species was studied. All the species could be divided into at least 3 clades, depending on the content of CLsat subfamilies in each genome: “saxicola”, “rudis”, and “mixta” lizards. CLsatI was found in all studied species, but in very different quantities; the “saxicola” group contained this subfamily predominantly. The “rudis” group also contained CLsatIII, and the “mixta” group carried considerable amounts of CLsatII. The highest concentrations of CLsatI and CLsatII were detected in 2 ground lizards — D. derjugini and D. praticola, respectively. D. parvula predominantly carried CLsatIII. CLsatIV was found only in the Crimean species D. lindholmi. The distribution patterns of satellite subfamilies show possible postglacial speciation within the genus Darevskia. A hybrid origin of species that possess 2 or 3 CLsat subfamilies and important clarifications to the systematics of the genus are proposed.

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The Caucasian parthenogenetic rock lizards of the L. saxicola complex probably originated by hybridisation of some bisexual species. We verified this hypothesis using a new approach based on comparison of repetitive DNA characters, which produce species-specific patterns (named `taxonprint`). The method relies on restriction endonuclease hydrolysis of genomic DNA, with the following 32P-end labeling and polyacrylamide gel electrophoretic separation of the fragments. The parthenogenetic species L. armeniaca and L. dahli possess specific features both of putative maternal L. mixta (in some taxonprints), and of paternal L. valentini (in other ones), whereas L. portschinskii and L. rudis also could be the paternal species. Parthenoclones L. unisexualis and L. uzzelli have the specific DNA features in several taxonprints of L. raddei or L. nairensis (which cannot be discriminated by taxonprints) which are supposed to be maternal species for L. unisexualis and paternal ones for L. uzzelli. The specific features of L. valentini (or L. portschinskii) are observed in L. unisexualis; L. uzzelli has not been investigated in this respect. Parthenogenetic L. rostombekovi also possesses properties of L. raddei or L. nairensis, but we have not be able to find any features of supposed paternal L. portschinskii in this parthenogenetic species.

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Multiple band patterns of DNA repeats in the 20–500-nucleotide range can be detected by digesting genomic DNA with short—cutting restriction endonucleases, followed by end labeling of the restriction fragments and fractionation in nondenaturing polyacrylamide gels. We call such band patterns obtained from genomic DNA ‘‘taxonprints’’ (Fedorov et al. 1992). Here we show that taxonprints for the taxonomic groups studied (mammals, reptiles, fish, insects—altogether more than 50 species) have the following properties: (1) All individuals from the same species have identical taxonprints. (2) Taxonprint bands can be subdivided into those specific for a single species and those specific for groups of closely related species, genera, and even families. (3) Each restriction endonuclease produces unique band patterns; thus, five to ten restriction enzymes (about 100 bands) may be sufficient for a statistical treatment of phylogenetic relationships based on polymorphisms of restriction endinuclease sites. We demonstrate that taxonprint analysis allows one to distinguish closely related species and to establish the degree of similarity among species and among genera. These characteristics make to use this phenomenon for phylogenetic aims (Cooke 1975; Christie and Skinner 1979; Brown and Dover 1979, 1980; Elizur et al. 1982; Hembelen et al. 1982; Buckland 1983; Dandieu et al. 1984; Lima de Faria et al. 1984; Shubina and Mednikov 1986; Turner et al. 1991), but this approach has not been extensively applied. In this paper we have reexamined the problem on the basis of our own preliminary results, partly published in Russian journals, confirming the ideas about possible correlations between evolution of DNA repeats and speciation (Fedorov et al. 1992; Grechko et al. 1993; Potapov and Ryskov 1993). We have demonstrated that the modified method designated ‘‘DNA taxonprint’’ (Fedorov et al. 1992) can be effectively used for revealing species—specific genomic markers in different taxonomic groups. These taxonprint markers are found to be helpful for evaluation of the degree of species similarity between species, genera, and families. More than 50 species from different taxa were studied.

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Several recent papers have reviewed the life and work of French herpetologist Louis Amédée Lantz. They have detailed the composition of his collections deposited in several museums. However, since then, several other important specimens from his collections deposited at the Natural History Museum (NHM, UK) have come to light and we here present all of them in detail. We discovered paralectotypes of Lacerta saxicola obscura Lantz & Cyrén (BMNH 1918.11.21.5–7), syntypes of Lacerta boemica Sukhov (BMNH 1960.1.4.26–30, BMNH 1965.337–342) and Lacerta viridis media Lantz & Cyrén (BMNH 1960.1.4.25, 1966.512). We also identified numerous specimens from the French Mediterranean islands in Lantz’s collection deposited at the NHM, some of which represent the first reported specimens of their species from certain islands. We here provide data on all these specimens. We also place the Mediterranean island specimens from the Lantz collection in their historical context and emphasize the historical and taxonomic value of these collections.

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An overview of the cases of introduction (both accidental and intentional) of amphibians and reptiles in the Caucasus and Crimea is provided. The introduction cases are systemized in accordance with the goals and ways of introduction and with regards to the expected scale of the impact and its nature. No negative consequences of the introduction of amphibian and reptile species in the Crimea and Caucasus are currently observed on any of the known examples. No cases of species naturalization, which the “invasion” term can be applied to, have been revealed. The importance of allochthonous populations as experimental sites to study microevolutionary processes and ecological adaptations of the species in new environmental conditions is discussed.

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Turkey is biogeographically diverse and consequently has a rich herpetofauna. As a result of active herpetological research, the number of species has steadily increased in recent years. I present here a new checklist of amphibian and reptile species distributed in Turkey, revising the nomenclature to reflect the latest taxonomic knowledge. In addition, information about the systematics of many species is also given. In total 35 (19.4%) amphibian and 145 (80.6%) reptile species comprise the Turkish herpetofauna. Among amphibians, 16 (45.7%) anurans and 19 urodelans (54.3%) are present. Among reptiles, 11 (7.6%) testudines, 71 (49%) saurians, 3 (2.1%) amphisbaenians and 60 (41.3%) ophidians are considered part of the herpetofauna. The endemism rate in Turkey is considered relatively high with a total of 34 species (12 amphibian species – 34.3% and 22 reptile species – 15.2%) endemic to Turkey, yielding a total herpetofaunal endemism of 18.9%. While 38 species have not been threat-assessed by the IUCN, 92 of the 180 Turkish herpetofaunal species are of Least Concern (LC), 13 are Near Threatened (NT), 10 are Vulnerable (VU), 14 are Endangered (EN), and 7 are Critically Endangered (CR). In addition, 6 species are in the DD (Data Deficient) category.

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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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Using a pair of primers selected for the loci Du215, Du281, and Du323 of Darevskia unisexualis, monolocus PCR analysis of orthologous loci was carried out in populations of the related parthenogenetic species D. armeniaca and in populations of bisexual parental species D. valentini and D. mixta. It was shown that the studied loci were polymorphic and represented in populations of D. armeniaca by several allelic variants. We cloned and sequenced PCR amplification products of the allelic variants of Du215, Du281, and Du323 loci. It was found that allelic differences in microsatellite loci were caused by variations in the number of tandem repeats in the microsatellite clusters and point mutations in the flanking regions. An interspecies comparison of the orthologous locus Du215 between parthenogenetic species D. armeniaca and parental species showed that two allelic variants of Du215 in D. armeniaca were inherited from the parental bisexual species D. mixta and D. valentini. The third allelic variant was not found in parental species and appeared due to mutation processes in genome of parthenospecies. For the first time, the information about the molecular nature of allelic polymorphism of these microsatellite loci of parthenogenetic species D. armeniaca was received in this study.

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The Bov-B LINE retrotransposon was first discovered in Ruminantia and was long considered to be specific for this order. Later, this mobile element was described in snakes and some lizard species. Analysis of phylogenetic relationships of Bov-B LINE elements from different ruminants, snakes, and lizard species led to the suggestion on horizontal transfer of this retrotransposon from Squamata to Ruminantia. In the Squamata group, Bov-B LINE element was found in all snakes and some lizard species examined. The element was not detected in the genomes of some species of the genera Lacerta and Podarcis. In the present study, using PCR amplification and sequencing of PCR products, Bov-B LINE element was identified in the genomes of parthenogenetic and bisexual species of the genus Darevskia (Lacertidae), as well as in such species as Lacerta agilis and Zootoca vivipara, where this retrotransposon had not been not detected before.

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Investigated the albumins from 31 species and subspecies of the genus Lacerta s.1. by means of the immunoloical techniue Micro-Complement-fixation. Dendrograms were computed by means of the ktch-MargJiash algorithm. Moreover the taxa of the Lacerta saxicola and the Lacerta danfordi comlexes were analyzed by electrophoresis concerning 14 genetic loci. The results were discussel together with karyological and genitalmorphological data so far known yielding the following relationships: Lacerta graeca shows a closer relationshi to the subgenus Podarcis as does the quite closely related species air L. dugesii and L. perspicikata. Lacerta Iaevis probabl is connected closely to Podarcis, too. Lacerta parva shows a closer relationship to the `small izards` than to the sub-genus Lacerta s. str. A clear decision concerning the position of the Lacerta danfordi complex according to chemosystematical data was not possible. It is isolated from the other species probably about as long as L. puma. Biochemical differences between its `species` are too small to confirm their taxonomical revalorisation by Eiselt and Schmidtler Within the Lacerta saxicola complex the investigated taxa show a close relationship. Lacerta praticola and L. derjugini were definitly assigned to this group.

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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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Restriction enzymes were used to assay variation among mitochondrial DNAs from parthenogenetic and sexual species of Lacerta. This permitted identification of the sexual species that acted as the maternal parent of the various hybrid-parthenogenetic lineages. Lacerta mixta was the maternal parent for both L. dahli and L. armeniaca, L. valentini was the maternal parent for L. uzzelli, and L. raddei was the maternal parent of L. rostombekovi. The maternal ancestry of L. unisexualis is not as clear. The sample of L. nairensis was very similar to one from a population of L. raddei and either species could be the maternal parent of L. unisexualis. The parthenogenetic species all had very low nucleotide diversity in absolute terms and in comparison to their sexual relatives. The close similarity between mtDNAs from the parthenogenetic species and their respective sexual maternal ancestor species provides strong evidence for the recent origin of the parthenogens. The low diversity of the parthenogens indicates that few females were involved in their origins; the maternal parents of L. dahli and L. armeniaca could have come from a single population. The patterns of mtDNA variation in Lacerta are very similar to those in Cnemidophorus and Heteronotia, establishing recent and geographically restricted origins as a general feature of parthenogenetic lizards.

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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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Rock lizards of the genus Darevskia are interesting research models due to their asexual reproduction. Ectoparasitic mites and ticks of these lizards are poorly known, despite some of these chelicerates being vector pathogens of humans and wildlife. Here we document and curate previously known data on ectoparasitic Acari of rock lizards and, based on our extensive survey, provide an annotated list of these ectoparasitic arthropods (six tick species, one macronyssid species, and seven chigger species). We also provide new host records (Ixodes ricinus on Darevskia caucasica, D. dryada, D. mixta, and D. szczerbaki; Haemaphysalis sulcata on D. rudis; Odontacarus saxicolis on D. brauneri); and new geographical records (O. saxicolis in Russia and Georgia).

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Rock lizards of the genus Darevskia are interesting research models due to their asexual reproduction. Ectoparasitic mites and ticks of these lizards are poorly known, despite some of these chelicerates being vector pathogens of humans and wildlife. Here we document and curate previously known data on ectoparasitic Acari of rock lizards and, based on our extensive survey, provide an annotated list of these ectoparasitic arthropods (six tick species, one macronyssid species, and seven chigger species). We also provide new host records (Ixodes ricinus on Darevskia caucasica, D. dryada, D. mixta, and D. szczerbaki; Haemaphysalis sulcata on D. rudis; Odontacarus saxicolis on D. brauneri); and new geographical records (O. saxicolis in Russia and Georgia).

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In this work, we tested the conditions for fulfilling the concept of geographic parthe- nogenesis by a comparative analysis of the breadth of the ecological niches of parental and par- thenogenetic lizards of the genus Darevskia with a various number of established hybridization events. Estimates of the breadth of ecological niches of the parthenogenetic species D. ros- tombekowi Nb = 0.6(±0.08) and parental bisexual species D. raddei raddei – Nb = 0.86(±0.9), D. portschinskii – Nb = 1.21(±0.17) showed that for this parthenogenetic species one of the most important conditions of geographic parthenogenesis is fulfilled, i.e. the niche breadth of the parthenogenetic species is smaller than its parental bisexual species. The niche breadth of another parthenogenetic species D. dahli Nb = 0.86(±0.12) is smaller than that of the «paternal» species D. portschinskii – Nb = 1.21(±0.17), but larger than that of the «maternal» species D. mixta Nb = 0.48 (±0.08), which only partially agrees with the condition of geographic par- thenogenesis. This mismatch is due to the fact that D. dahli was formed as a result of several independent hybridization events, which resulted in the formation of multiple clonal lines de- rived from different parental pairs of D. portschinskii and D. mixta.

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After a brief description of Georgia’s landscape the author reports on the lizards of the family Lacertidae that were found during a herpetological trip in May 2012. In addition, a list of the recorded herpetological taxa is presented.

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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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An integrated approach for constructing maps of suitable habitats and ecological niches of parthenogenetic and their parental species of the genus Darevskiain the Caucasus is presented. It is shown that this approach is a powerful tool for analyzing species-specific requirements of lizards for the habitat and differentiating their niches in the multidimensional space of predictor variables.

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Studies of geographical distribution of parthenogenetic Darevskia armeniaca and its parental species D. mixta and D. valentini can extend our knowledge in terms of their biology and prediction of expansion of their ranges owing to increasing anthropogenic impact and global climate change. We studied the rock lizards of the genus Darevskia because their ecology, biology and potential ranges have not been well studied. Our objectives were: (1) to create maps of the potential geographical distribution of the lizard species; (2) to identify bioclimatic, topographic and landscape variables that determine their potential ranges; (3) to establish similarities and differences in ecological conditions of lizard localities between the parthenogenetic lizard and its parental species. We extended the available published data set with our own field survey records to assess effects of environmental factors on ecological niches of the lizards and their distribution in Transcaucasia and Asia Minor using methods of ordination and species distribution models (SDMs). Our results show that the main drivers regulating the distribution of Darevskia spp. are climatic, topographic and land cover/use. High SDM performance estimated as a Boyce index ~0.917 proved that we had incorporated the most important predictor variables for describing ecological niches of the lizard species. We used an ordination method to compare niches in terms of their overlap, similarity, and niche shifts of the parthenogenetic species relative to its parental species. Habitat preference of D. mixta was determined by altitude, vegetation type, high precipitation during the warmest season, low humidity variation, and low insolation. Habitats of D. valentini were predicted to be located at the highest altitude in the zone of subalpine meadows, low temperature during the dry months, low precipitation during the warm months, an average coefficient of seasonal variation in humidity, high insolation, and a short distance to roads. We suggest that the centroid of the niche of the “daughter” species, D. armeniaca, occupies an intermediate position along environmental gradients relative to that of its parental species with only one exclusion. The coefficient of humidity variation in D. armeniaca differed from that of its parental species. In general, we predicted that ecological niches of parthenogenetic and parental species overlapped by 36%, however, the ecological niche of D. armeniaca was similar to that of its “paternal” species D. valentini. We demonstrate that the parthenogenetic D. armeniaca prefers mountain forest, meadow, steppe and human-disturbed habitats, while the “maternal” species D. mixta inhabits mainly forest habitats and the “paternal” species D. valentini commonly occurs in mountain meadow and mountain steppe habitats in the subalpine zone. These results can be used by environment conservation organizations to preserve the most important habitats of these lizards.

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The hypothesis of hybridogenous origin of lacertid parthenogenetic species was verified by RAPD method with several arbitrary primers. The hypothesis appeared to be correct as both parthenogenetic lizard DNAs contain only the RAPD loci of putative parental bisexual species and practically no ones specific for parthenospecies. The most probable parentals are L. mixta and L. portschinskii for L. dahli, and some of the populations of L. raddei/nairensis complex and L. portschinskii, too, for L. rostombekovi.

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Elements of the herpetofauna are in the author`s opinion of great importance for the zoogeographical division of the Palaearctic region. It is suggested that this region be divided into the following four subregions: 1/ arctic, 2/ boreal Euro-Siberian, 3/ bo- real Himalayan-Manchurian and 4/ Mediterranean-Central-Asiatic.

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We compared the distributions, abundances and ecological requirements of parthenogenetic lizard Darevskia ‘dahli’ and its bisexual progenitors, D. portschinskii and D. mixta, in Georgia. We developed a regression model relating the species abundances with the distribution of climates. Darevskia portschinskii lives in warmer and drier climates than D. mixta; D. ‘dahli’ has the intermediate requirements. Temperature is more important than humidity for D. portschinskii, humidity is more important for D. mixta and both temperature and humidity are important for D. ‘dahli’. Suitable habitats of all three species overlap broadly; however, the observed ranges partly overlap only for D. ‘dahli’ and D. portschinskii. The observed abundance of each species, related to its predicted abundance, is lower at the sites with potential competitors. Darevskia ‘dahli’ occupies a higher proportion of the suitable habitats and has higher abundances than the progenitor species. Competition with D. ‘dahli’ is an important factor determining current distribution pattern of D. portschinskii and D. mixta. The parthenogen is a stronger competitor than the bisexual breeders and potential advantages of the bisexual reproduction remain unrealized in the given temporal and spatial scale. To explain domination of bisexually breeding lizards on the global scale, considering climate changes in geological timescale is necessary.

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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

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Background: The majority of parthenogenetic vertebrates derive from hybridization between sexually reproducing species, but the exact number of hybridization events ancestral to currently extant clonal lineages is difficult to determine. Usually, we do not know whether the parental species are able to contribute their genes to the parthenogenetic vertebrate lineages after the initial hybridization. In this paper, we address the hypothesis, whether some genotypes of seven phenotypically distinct parthenogenetic rock lizards (genus Darevskia) could have resulted from back-crosses of parthenogens with their presumed parental species. We also tried to identify, as precise as possible, the ancestral populations of all seven parthenogens. Results: We analysed partial mtDNA sequences and microsatellite genotypes of all seven parthenogens and their presumed ansectral species, sampled across the entire geographic range of parthenogenesis in this group. Our results confirm the previous designation of the parental species, but further specify the maternal populations that are likely ancestral to different parthenogenetic lineages. Contrary to the expectation of independent hybrid origins of the unisexual taxa, we found that genotypes at multiple loci were shared frequently between different parthenogenetic species. The highest proportions of shared genotypes were detected between (i) D. sapphirina and D. bendimahiensis and (ii) D. dahli and D. armeniaca, and less often between other parthenogens. In case (ii), genotypes at the remaining loci were notably distinct. Conclusions: We suggest that both observations (i-ii) can be explained by two parthenogenetic forms tracing their origin to a single initial hybridization event. In case (ii), however, occasional gene exchange between the unisexual and the parental bisexual species could have taken place after the onset of parthenogenetic reproduction. Indeed, backcrossed polyploid hybrids are relatively frequent in Darevskia, although no direct evidence of recent gene flow has been previously documented. Our results further suggest that parthenogens are losing heterozygosity as a result of allelic conversion, hence their fitness is expected to decline over time as genetic diversity declines. Backcrosses with the parental species could be a rescue mechanism which might prevent this decline, and therefore increase the persistance of unisexual forms.

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Spatial and temporal constraints on dispersal explain the absence of species from areas with potentially suitable conditions. Previous studies have shown that post-glacial recolonization has shaped the current ranges of many species, yet it is not completely clear to what extent interspecific differences in range size depend on different dispersal rates. The inferred boundaries of glacial refugia are difficult to validate, and may bias spatial distribution models (SDMs) that consider post-glacial dispersal constraints. We predicted the current distribution of 12 Caucasian forest plants and animals, factoring in the effective geographical distance from inferred glacial refugia as an additional predictor. To infer glacial refugia, we tested the transferability of the current SDMs based on the distribution of climatic variables, and projected the most transferable ones onto two climate scenarios simulated for the Last Glacial Maximum (LGM). We then calculated least-cost distances from the inferred refugia, using elevation as a friction surface, and recalculated the current SDMs incorporating the distances as an additional variable. We compared the predictive powers of the initial with the final SDMs. The palaeoclimatic simulation that best matched the distribution of species was assumed to represent the closest fit to the true palaeoclimate. SDMs incorporating refugial distance performed significantly better for all but one studied species, and the Model for Interdisciplinary Research on Climate (MIROC) climatic simulation provided a more convincing pattern of the LGM climate than the Community Climate System Model (CCSM) simulation. Our results suggest that the projection of suitable habitat models onto past climatic conditions may yield realistic boundaries of glacial refugia, and that the current distribution of forest species in the study region is strongly associated with locations of former refugia. We inferred six major forest refugia throughout western Asia: (1) Colchis; (2) western Anatolia; (3) western Taurus; (4) the upper reaches of the Tigris River; (5) the Levant; and (6) the southern Caspian basin. The boundaries of the modelled refugia were substantially broader than the refugia boundaries inferred solely from pollen records. Thus, our method could be used to: (1) improve models of current species distributions by considering the dispersal histories of the species; and (2) validate alternative reconstructions of palaeoclimate with current distribution data.

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A new species of rock lizards of the genus Darevskia Arribas, 1999 — Darevskia arribasi sp. nov. is described from vicinity of Ertso Lake in South Ossetia. In comparison of Darevskia arribasi sp. nov. with other species of the “saxicola-brauneri” complex [D. lindholmi (Szczerbak, 1962), D. saxicola (Eversmann, 1834), D. brauneri (Mehely, 1909) (including D. b. brauneri, D. b. myusserica Doronin, 2011, D. b. darevskyi (Szczerbak, 1962), and D. szczerbaki (Lukina, 1963)], the new species is characterized by the smallest body size among all representa- tives of this complex Lxx — 55 – 62 mm; }} — 58 – 63 mm. The number of scales around the middle of the body (Sq.) in D. arribasi sp. nov. (52 – 58, more often 54 – 56) also significantly less than for D. saxicola sensu lato in generally. Along the throat from ear to ear fold there are 36 – 42 scales, less than in D. saxicola sensu lato. Two large preanal shields present in front of the anal shield in half of the individuals examined; in a quarter of in- dividuals on both sides of the small central preanal there are by one enlarged lateral preanal shield, in another quarter all preanal shields are of the same size. Central temporal (Massetericum) always developed; always six pair of mandibulars, three in contact; collar straight, extremely rarely slightly serrated; ribs on the caudal scales are expressed to some extent; rostral usually separated from frontonasal by nasal shields. The coloration of adult males is olive-lettuce, or olive-brown from above; adult females are grey-brown; juvenile coloration coffee-brown with the blue and black spots on the edge of the outer ventral shields at the middle of trunk. Taxonomical status of new species is well supported with result of analysis of the mitochondrial cytochrome b data.

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A new species of rock lizards of the genus Darevskia Arribas, 1999 — Darevskia arribasi sp. nov. is described from vicinity of Ertso Lake in South Ossetia. In comparison of Darevskia arribasi sp. nov. with other species of the “saxicola-brauneri” complex [D. lindholmi (Szczerbak, 1962), D. saxicola (Eversmann, 1834), D. brauneri (Mehely, 1909) (including D. b. brauneri, D. b. myusserica Doronin, 2011, D. b. darevskyi (Szczerbak, 1962), and D. szczerbaki (Lukina, 1963)], the new species is characterized by the smallest body size among all representa- tives of this complex Lxx — 55 – 62 mm; }} — 58 – 63 mm. The number of scales around the middle of the body (Sq.) in D. arribasi sp. nov. (52 – 58, more often 54 – 56) also significantly less than for D. saxicola sensu lato in generally. Along the throat from ear to ear fold there are 36 – 42 scales, less than in D. saxicola sensu lato. Two large preanal shields present in front of the anal shield in half of the individuals examined; in a quarter of in- dividuals on both sides of the small central preanal there are by one enlarged lateral preanal shield, in another quarter all preanal shields are of the same size. Central temporal (Massetericum) always developed; always six pair of mandibulars, three in contact; collar straight, extremely rarely slightly serrated; ribs on the caudal scales are expressed to some extent; rostral usually separated from frontonasal by nasal shields. The coloration of adult males is olive-lettuce, or olive-brown from above; adult females are grey-brown; juvenile coloration coffee-brown with the blue and black spots on the edge of the outer ventral shields at the middle of trunk. Taxonomical status of new species is well supported with result of analysis of the mitochondrial cytochrome b data.

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The results of five expeditions (1995, 1996, 2007, 2011, and 2012) to the north-eastern and eastern Turkey are presented. These data were collected from the Pontic (Lazistan) Ridge, Choroch River basin, and the upper flow basins of the Aras River, Kura River, Euphrates River, Tiger River, Dogankent (Kharshit) River, and the Van Lake basin. In total, 2 Caudata, 6 Anura, 2 Testudines (3 subspecies), 25 Sauria (30 subspecies) and 21 Serpentes species were found.

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Five proteins (mannosephosphate isomerase, glucosephosphate isomerase, lactate dehydrogenase, creatine kinase, hemoglobin) were examined for six bisexual Transcaucasian taxa related to Lacerta saxicola (Lacerta valentini, L. portschinskii, L. raddei raddei, L. r. nairensis, L. mixta, L. parvula) and four unisexual taxa (Lacerta armeniaca, L. dahli, L. rostombekovi, L. unisexualis). Heterozygosity in the bisexual taxa was very limited for this sample of proteins. All individuals examined of each unisexual were heterozygous at loci specifying at least two of these proteins (L. armeniaca: mannosephosphate isomerase and creatine kinase; L. dahli, mannosephosphate isomerase and hemoglobin; L. rostombekovi, glucosephosphate isomerase, mannosephosphate isomerase and hemoglobin; L. unisexualis, glucosephosphate isomerase, mannosephosphate isomerase and creatine kinase). High levels of heterozygosity in unisexuals appears to result from the hybrid origin of the unisexuals. The exact combinations of alleles present in unisexuals would readily result from certain crosses among the bisexuals, and from no others. The first point supports the hypothesis that hybridization accounts for the observed heterozygosity, the second identifies, biochemically at least, the probable parents. On these biochemical grounds, L. armeniaca arose by hybridization of L. valentini and L. mixta; L. unisexualis from L. valentini and L. r. nairensis; L. rostombekovi from L. r. raddei and L. portschinskii; and L. dahli from L. portschinskii and L. mixta. With regard to altitudinal distribution, vegetational associations and geographic distribution, each unisexual species appears to be intermediate between its putative parental species. L. armeniaca, L. unisexualis and L. rostombekovi all live in drier situations than either parental species. L. dahli is an exception since it occupies slightly more moist habitats than L. portschinskii. Biogeographical considerations appear to place the age of L. unisexualis and L. rostombekovi at greater than 5000 years. It is possible that their occupancy of more extreme habitats than their parental species represents a relic ecology, reflecting the adaptations of the parental bisexual species when the unisexual species arose, rather than a weed habitat into which they moved to escape from competition with their parental species. The fixed heterozygosity of the unisexual species of Lacerta indicates that the restitution of somatic diploidy results either from a premeiotic endoduplication without cytokinesis, or from fusion of the female pronucleus with one of the second division meiotic products of the first polar nucleus. The first mechanism is inconsistent with the number of bivalents reported, the second is otherwise unknown in organisms in which the first polar nucleus becomes a polar body. The bisexual taxa are treated as several distinct species, four pairs of which are partly sympatric with little or no hybridization. Morphological and ecological differences between the other taxa are so great that there seems little question about specific distinctness. The degree of biochemical and morphological difference between these non-sympatric taxa is as great as that between those that do occur sympatrically without fusing. The formation of parthenogenetic species as a result of past hybridization between some pairs indicates a great selective disadvantage to these pairs of hybridizing, and is thus compelling evidence that the two members of each pair are not conspecific.

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We genotyped multiple populations of all seven parthenogenetic species of rock lizards, genus Darevskia, as well as their putative sexual parental populations, using double digest RAD sequencing genomic markers. Taking advantage of the conserved homology of the ZW/ZZ sex chromosomes among lacertid lizards, we aligned our short sequence reads to a reference Z chromosome assembly of the common wall lizard Podarcis muralis. This provided unique insight into the origin of all-female hybrid populations, which inherited their single Z chromosome exclusively from a paternal ancestor. The mapped Z-linked loci were used to construct a robust time-calibrated phylogeny. In each parent–offspring species pair, the geographically nearest population of the paternal species was identified as the most likely ancestor of the respective parthenogen, mirroring the trend observed previously on the maternal side in mitochondrial DNA. The estimated splits between the sampled paternal sexual ancestors and their daughter species occurred much earlier than suggested previously and during two narrow time periods: (1) the parthenogenetic Darevskia armeniaca, D. dahli, D. uzzelli and D. rostombekowi dated back to ~0.5 or ~0.9 Mya, depending on the calibration point used, while (2) D. bendimahiensis, D. sapphirina and D. unisexualis appear to have diverged ~1 or ~2 Mya.