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The skeletochronological method has been used to assess age distribution and age-related differences in body size among populations of the parthenogenetic lizards Darevskia sapphirina, D. uzzelli, D. armeniaca and D. unisexualis from Turkey and Armenia. The age distribution between D. armeniaca and D. unisexualis did not significantly differ and ranged from 1 to 8 years. Maximum age for both D. uzzelli and D. sapphirina was 6 years, and 8 years for both D. unisexualis and D. armeniaca. In all the studied species, individuals reached sexual maturity after third hibernation. According to patterns of growth marks resorption, D. sapphirina is distinguished from all other rock lizards of genus Darevskia by a narrowest periosteal bone as result of high rate of endosteal resorption resulting in complete destruction of hatchling line and line of the first hibernation.

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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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The present study is on the morphologies and sizes of peripheral blood cells (erythrocytes, leukocytes, and thrombocytes) on blood smears, stained with Wright`s stain, in some lacertid lizards species [Apathya cappadocica (Werner, 1902), Acanthodactylus boskianus (Daudin, 1802), Acanthodactylus harranensis Baran et al. 2005, Anatolacerta danfordi (Günther, 1876), Darevskia praticola (Eversmann, 1834), D. uzzelli (Darevsky and Danielyan, 1977), D. valentini (Boettger, 1892), Parvilacerta parva (Boulenger, 1887), Lacerta pamphylica Schmidtler, 1975, L. trilineata Bedriaga, 1886, L. viridis (Laurenti, 1768), Ophisops elegans Menetries, 1832, Mesalina brevirostris Blanford, 1876, Podarcis muralis (Laurenti, 1768), P. sicula (Rafinesque-Schmaltz, 1810), Timon princeps (Blanford, 1874)] from Turkey. As a result of our survey, it was determined that the blood cells of the investigated species are shows significant variations in sizes and of leukocytes, agranulocytic leukocytes (lymphocytes and monocytes) are present as predominant cells. Moreover, of granulocytes, neutrophils were no observed in A. danfordi, D. praticola, D. uzzelli, and P. parva.

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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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Die Autotren berichten über zwei Aufsammlungen von Amphibien und Reptilien aus dem Gebiet der ostanatolischen Städte Erzurum, Iğdir, Kars und Ardahan. Das Material umfaßt drei Anurentaxa, eine Schildkrötenform, 11 Eidechsen- und 11 Schlangenarten in 172 Exemplaren. Aufgelistete Arten: Bufo viridis, Rana ridibunda complex, Rana camerani, Testudo graeca armeniaca, Phrynocephalus persicus, Eremias pleskei, Eremias strauchi, Lacerta agilis brevicaudata, Parvilacerta parva, Darevskia parvula, Darevskia raddei, Darevskia valentini valentini, Darevskia uzzelli, Lacerta trilineata, Ophisops elegans, Typhlops vermicularis, Eryx jaculus turcicus, Haemorrhois ravergieri, Hierophis schmidti, Platyceps najadum, eirenis modestus, Eirenis punctatolineatus, Coronella austriaca, natrix natrix persa, Natrix tessellata, Vipera wagneri.

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Lacertca raddei and Lacerta nairensis have been recognized as two separate species based on morphology and behavior, and each has been implicated as a sexual parent of different parthenogenetic forms. However, recent mitochondrial DNA work failed to distinguish these two as separate species. We examined genetic diversity at 36 allozyme loci from six populations of L. nairensis and four populations of L. raddei. There were no fixed allelic differences between the two. Mean heterozygosity was slightly higher among populations of L. raddei than among populations of L. nairensis. A Distance Wagner phenogram showed that the northernmost population of L. raddei clustered with the L. nairensis populations; the other L. raddei populations clustered together. We suggest that L. raddei and L. nairensis may not be separate species, a finding which has important implications for determining the origins of some parthenogenetic Lacerta.

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In the herpetological collection of ZFMK 528 scientific species group names are represented by type materi- al. Of these, 304 names are documented by primary type specimens (onomatophores) while for 224 further names sec- ondary type specimens (typoids) are available, ranging chronologically from 1801 to 2010. The list is a shortened pred- ecessor of a comprehensive type catalogue in progress. It lists name bearing types with their catalogue numbers includ- ing information on further type series members also in other institutions, while secondary types are listed only by pres- ence, both in ZFMK and other collections including holotype repositories. Geographic origin and currently valid names are also provided.

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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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Due to its geographic location, the Caucasus region connects species from three diferent continents in a heterogeneous landscape, creating an environment prune to the development of speciation events and multiple endemisms. Among them, the lacertid genus Darevskia is a group of rock lizards radiating and diversifying in the region. Among their highly polymorphic members a number of parthenogenetic forms are present result from the hybridisation between bisexual Darevskia species. However, the origin of these forms lacks an explicit spatiotemporal context. One of the most interesting bisexual species in the group is Darevskia raddei which is responsible for the motherhood of some unisexual forms, namely D. unisexualis, D. uzzeli and D. bendimahiensis and D. sapphirina). Fruthermore, this species is considered conspeciic to D. nairensis and D. (raddei) vanensis, two forms of unclear status which link to the parthenogenetic forms need to be clariied. This, this study aims to reach a global comprehension of the three putative bisexual taxa within of the D. raddei complex (D. raddei, D. nairensis and D. (raddei) vanensis), and their phylogenetic relationships with the parthenogenetic forms they theoretically parented. A phylogenetic analysis was conducted on samples of the D. raddei complex, ranging from Turkey, Armenia, Georgia and Iran. Maximum Likelihood and Bayesian methods were applied on a combination of mitochondrial and nuclearmarkers. Namely, three mtDNA (cytochrome b, ND4 and 12s) and two nDNA (MC1R and c-mos) markers were used. Our results conirm that Darevskia raddei (sensu lato) is the proposed maternal species for at least D. unisexualis, D. uzzeli, D. bendimahiensis, D. sapphirina and D. rostombekowi, as already supported by previous studies. However, it does not support a genetic diferentiation between the three forms described within the complex, which are to be considered conspeciic. Moreover, there is reinforced evidence that the three parthenogenetic forms considered arose more than once in the history of the genus, from diferent lineages of the bisexual parents.

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Darevskia rock lizards include both sexual and parthenogenetic species, mostly distributed in the heterogeneous and ecologically diverse Caucasus. The parthenogenetic species originated via directional hybridogenesis, with only some of the sexual species known to serve as parentals. However, it remains unclear when and where these events happened and how many parental lineages were involved. A multilocus phylogeographic analysis was performed on the parthenogens D. unisexualis, D. bendimahiensis and D. uzzeli, and their putative maternal species D. raddei. Results show the parthenogenetic species all have relatively recent origins, approximately 200–70 kyr ago, and at least three hybridization events were involved in their formation. Ecological niche models identify the region where hybridization events leading to the formation of D. unisexualis took place, namely in the northeast of the current distribution. Models also suggest that the sexual D. raddei might have undergone a habitat shift between the Last Interglacial and the Last Glacial Maximum.

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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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Allozyme electrophoresis of four sibling parthenogenetic Caucasian rock lizards Darevskia unisexualis, D.uzzelli, D.sapphirina, and D.bendimahiensis found seven clones and five variable loci. The data supported the hypothesis that D.raddei and D.valentini are the parental species of all four parthenogens. Variation patterns in Darevskia were summarized. Species that originated from a single F1 typically consisted of one widespread clone with a few rare clones. Species with multiple origins displayed variation only slightly higher than species with a single origin. This is contrary to other genera of parthenogenetic lizards, in which cases massive clonal variations were observed.

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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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In this study, we aimed to determine the amphibian and reptile species distributed in Agri province (Turkey), as well the major factors threatening the species. For this purpose, we conducted 4 field excursions (20 days totally) at 223 different point, covering all the squares of 1:25.000 layout map. As a result of the literature and field survey, we recorded 4 anuran (Pseudepidalea variabilis, Pelophylax ridibundus, Rana camerani, R. macrocnemis), 2 chelonian (Mauremys caspica, Testudo graeca), 16 lizard (Paralaudakia caucasia, Phrynocephalus horvathi, Ablepharus bivittatus, Trachylepis aurata, Darevskia bendimahiensis, D. raddei, D. valentini, D. sapphirina, D. unisexualis, D. uzzelli, Eremias suphani, E. strauchi, E. pleskei, Lacerta media, Ophisops elegans, Parvilacerta parvd) and 14 snake (Typhlops vermicularis, Dolichophis jugularis, D. schmidti, Eirenis eiselti, E. modestus, E. collaris, Coronella austriaca, Hemorrhois ravergieri, Natrix natrix, N. tessellata, Platyceps najadum, Eryx jaculus, Montivipera wagneri, M raddei) species in Agri province, which is totally 4 amphibians and 32 reptiles. Three Anatolian endemic species (Darevskia sapphirina, Eirenis eiselti, Montivipera wagneri) and 7 species more was recorded in Agri as s first time in the literture. Taking into account the very limited herpetofaunal information available in the literature for Agri province, a significant contribution was made with this work. This study was conducted as a part of `The Ministry of Forestry and Water Affairs, General Directorate of Nature Conservation and National Parks National Biodiversity Inventory and Monitoring Project`.

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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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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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A phylogeny of Caucasian rock lizards (genus Darevskia, formerly Lacerta) was reconstructed using mitochondrial DNA sequence and allozyme data. All 15 bisexual species grouped into three major clades: the caucasica, saxicola and rudis clades. Unisexual Darevskia originate from inter-clade hybridization, never from within clades. Only two clades, the caucasica clade and the rudis clade, were involved in forming unisexuals; the saxicola clade was never involved. Furthermore, the hybridization is directional in that the caucasica clade contributed only maternal parents and the rudis clade only paternal parents. The formation of unisexual species is best explained by sexually directional phylogenetic constraints. We hypothesize that the causative agents are likely to be genes linked with the sex chromosomes within the parental sexual species.

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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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Darevskia uzzelli (Darevsky et Danielyan, 1977) is a parthenogenetic lacertid lizard endemic to a restricted range in the vicinity of Horasan and Selim, NE Anatolia. Twenty specimens were captured from two different populations and analyzed for gastrointestinal helminthes. Only one male and one female of the nematode Skrjabinodon sp. (Pharyngodonidae) were found in two of the searched hosts. In consequence, the infection and diversity parameters were extremely low ant suggest a depauperate helminth community for this parthenogentic lacertid lizard. In fact, the infection and diversity values fall among the lowest within the Palaearctic saurians. Comparison of our results with those known for the parthenogenetic teiid species of the New World genus Aspidoscelis Fitzinger, 1843 (former Cnemidophorus), suggests some features that may characterize the helminth faunas of unisexual lizards: (i) very poor helminth communities; (ii) they share parasites with most other congeners; (iii) Pharyngodonidae nematodes are the most important parasites in these depauperate helminth communities. Some hypothesis on the evolution on sex suggest that identical clonal lineages should be more vulnerable to parasitism over time than genetically diverse sexual lineages. If so, parthenogenetic lizards should harbour more parasites than their recent unisexual parental ancestors. Nevertheless, some other studies do not corroborate that hypothesis. Although we have not compared the helminth communities of D. uzzelli with those of D. valentini (Boettger, 1892) and D. raddei (Boettger, 1892) (parental lineages), present results also deviate from the above mentioned hypothesis. An alternative possible reason for this extremely poor helminthfauna found in D. uzzelli may be the decreasing of opportunities for interchanging helminthes with direct life cycles, since less intra- and interespecific contacts are expected among unisexual lizards than among bisexual ones.

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Specimens of three species of parthenogenetic lizards (Darevskia uzzelli, D. bendimahiensis, and D. sapphirina) from northeastern Turkey were examined for gastrointestinal parasites. Only one species, the nematode Spauligodon saxicolae (Pharyngodonidae), was found. The extremely low infection and diversity parameters, falling among the lowest within the Palaearctic saurians, support depauperate helminth communities for these parthenogenetic lacertid lizards. Our results suggest that parthenogenetic Darevskia follow a pattern of parasitism similar to other unisexual lizards (i.e. Aspidocelis). The low rates of infection and diversity may be explained by the decreasing opportunities for interchanging helminths rather than factors of susceptibility of unisexual hosts.

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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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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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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.

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As a result of a literature survey and field studies covering all regions of the Turkish Province of Agri, the authors found the area inhabited by three anuran, two chelonian, 16 lizard and 14 snake species. The records and their locations are presented in a map, a table and an Appendix. In the field studies the present paper is based upon Mauremys caspica, Ablepharus bivittatus, Parvilacerta parva, Eremias pleskei, Xerotyphlops vermicularis, Natrix natrix, Coronella austriaca, Eirenis eiselti, Dolichophis jugularis, Dolichophis schmidti, Platyceps najadum and Montivipera wagneri were recorded for the first time in the Province of Agri.