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Öğe It takes two to tango - Phylogeography, taxonomy and hybridization in grass snakes and dice snakes (Serpentes: Natricidae: Natrix natrix, N. tessellata)(Senckenbergische Naturforschende Gesellschaft, 2021) Asztalos, Marika; Ayaz, Dinçer; Bayrakçı, Yusuf; Afşar, Murat; Tok, Cemal Varol; Kindler, Carolin; Jablonski, Daniel; Fritz, UweUsing two mitochondrial DNA fragments and 13 microsatellite loci, we examined the phylogeographic structure and taxonomy of two codistributed snake species (Natrix natrix, N. tessellata) in their eastern distribution area, with a focus on Turkey. We found evidence for frequent interspecific hybridization, previously thought to be extremely rare, and for backcrosses. This underscores that closely related sympatric species should be studied together because otherwise the signal of hybridization will be missed. Furthermore, the phylogeographic patterns of the two species show many parallels, suggestive of a shared biogeographic history. In general, the phylogeographies follow the paradigm of southern richness to northern purity, but the dice snake has some additional lineages in the south and east in regions where grass snakes do not occur. For both species, the Balkan Peninsula and the Caucasus region served as glacial refugia, with several mitochondrial lineages occurring in close proximity. Our results show that the mitochondrial divergences in both species match nuclear genomic differentiation. Yet, in the former glacial refugia of grass snakes there are fewer nuclear clusters than mitochondrial lineages, suggesting that Holocene range expansions transformed the glacial hotspots in melting pots where only the mitochondrial lineages persisted, bearing witness of former diversity. On the other hand, the deep mitochondrial divergences in N. tessellata across its entire range indicate that more than one species could be involved, even though lacking microsatellite data outside of Turkey prevent firm conclusions. On the contrary, our microsatellite and mitochondrial data corroborate that N. megalocephala is invalid and not differentiated from sympatric populations of N. natrix. For Cypriot grass snakes, our analyses yielded conflicting results. A critical assessment of the available evidence suggests that N. natrix is a genetically impoverished recent invader on Cyprus and taxonomically not distinct from a subspecies also occurring in western Anatolia and the southern Balkans. Based on combined mitochondrial and nuclear genomic evidence we propose that for grass snakes the following subspecies should be recognized in our study region: (1) Natrix natrix vulgaris Laurenti, 1768, southeastern Central Europe and northern Balkans; (2) Natrix natrix moreotica (Bedriaga, 1882), southern Balkans, western Anatolia, and Cyprus; and (3) Natrix natrix scutata (Pallas, 1771), eastern Anatolia, Caucasus region, Iran, northeastern distribution range (from eastern Poland and Finland to Kazakhstan and the Lake Baikal region). Thus, Natrix natrix cypriaca (Hecht, 1930) becomes a junior synonym of N. n. moreotica and Natrix natrix persa (Pallas, 1814) becomes a junior synonym of N. n. scutata. Due to insufficient material, we could not resolve the status of Natrix natrix syriaca (Hecht, 1930) from the Gulf of İskenderun, southeastern Turkey.Öğe Mitochondrial diversity of European pond turtles (Emys orbicularis) in Anatolia and the Ponto-Caspian Region: Multiple old refuges, hotspot of extant diversification and critically endangered endemics(Springer Heidelberg, 2009) Fritz, Uwe; Ayaz, Dincer; Hundsdoerfer, Anna K.; Kotenko, Tatiana; Guicking, Daniela; Wink, Michael; Tok, Cemal VarolThe European pond turtle, Emys orbicularis (Linnaeus, 1758), is one of the world's most widely distributed chelonian species. We investigated its mitochondrial phylogeography and demography using similar to 1300 cyt b sequences from the entire range, with a focus on the eastern part, in particular on Turkey, where the species currently suffers massive losses. Coloration data from > 1450 turtles were compared with mtDNA differentiation to assess the validity of the currently accepted subspecies from Turkey, the Black Sea Region, the Transcaucasus, and Iran. Our study region harbors considerable part of the mtDNA diversity of Emys, including a newly discovered lineage and 16 new haplotypes. In this area corresponding to approximately one-third of the entire distribution range, six out of the ten mitochondrial lineages and about half of all 72 haplotypes occur. Two mitochondrial lineages (VIII, X) are confined to small ranges along the southern coast of Turkey, another lineage (I) occupies the remainder of Turkey, the entire Black Sea Region, and the north-eastern part of the species' range. In the south-western corner of the Black Sea and in the Aegean Region, two lineages (II, IV) occur that have their main distribution areas farther west. In the Transcaucasus and northern Iran, another endemic lineage (VII) is found. Lineage I is the largest and most diverse of all lineages and has its greatest diversity in Anatolia. Phylogeographic and demographic data suggest Anatolia as an ancient glacial refuge for turtles harboring mitochondrial lineages I, VIII and X, and that Anatolia and the Black Sea coasts constitute a hotspot for a younger burst of diversification within lineage I. These two regions correspond to the glacial refuge from which lineage I turtles recolonized more northerly parts of the range in the Holocene; lineage II represents an off-shoot of lineage I that became isolated in a westward-located refuge in the south-eastern Balkans during a previous Pleistocene glacial. Our data on coloration indicate that Such characters have only limited value for delineating evolutionarily significant units. We propose to reduce the number of subspecies using mtDNA lineages as arbiter, and to recognize three subspecies as valid in Turkey, the Black Sea Region, the Transcaucasus and Iran: Emys orbicularis orbicularis (mtDNA lineage 1); E. o. eiselti Fritz et al., 1998 (X); and E. o. persica Eichwald, 1831 (VII). However, the Southern Turkish lineage VIII most probably represents an additional undescribed subspecies. Both southern Turkish endemics are critically endangered, with only three surviving populations of fewer than 30 adults each. We recommend establishing sanctuaries for them, and including them in the IUCN Red List. (C) 2009 Gesellschaft fur Biologische Systematik. Published by Elsevier GmbH. All rights reserved.Öğe On the Brink of Extinction: Results of a 20-Year Quest for Eiselt's Pond Turtle (Emys orbicularis eiselti) in Southeastern Turkey(Chelonian Research Foundation, 2021) Ayaz, Dinçer; Bayrakçı, Yusuf; Çiçek, Kerim; Ihlow, Flora; Tok, Cemal Varol; Fritz, UweEiselt’s pond turtle (Emys orbicularis eiselti) was described in 1998, based on only 4 museum specimens collected in the 1960s and 1970s. Its distribution range has been massively reduced by large-scale drainage measures and only little suitable habitat remains near the Turkish–Syrian border. During 20-yr-long fieldwork we could locate only 18 individuals of this subspecies. We estimate the number of surviving Eiselt’s pond turtles to be less than 100 mature individuals in the wild. The distribution range (area of occupancy) in the Amik Maras Rift Valley shrank from originally 11,612 km2 to only 206 km2 at present (approx. 2%), qualifying E. o. eiselti as a Critically Endangered taxon. Without immediate conservation measures and the strict protection of the remaining habitat, the subspecies will soon be extinct.Öğe Population estimate and body size of European pond turtles (Emys orbicularis) from Pazaragac (Afyonkarahisar/Turkey)(Walter De Gruyter Gmbh, 2007) Ayaz, Dincer; Fritz, Uwe; Tok, Cemal Varol; Mermer, Ahmet; Tosunoğlu, Murat; Afsar, Murat; Cicek, KerimData on population size, adult sex ratio, body size and mass are provided for a population of the turtle Emys orbicularis near Pazaragac (Afyonkarahisar/Turkey). Using the mark-recapture method (triple catch), a population size of 664 turtles was estimated (95% confidence interval, range 332-996), corresponding to a density of 83 turtles per hectare (range 41.5-124.5). The adult sex-ratio was significantly skewed in favor of males (2.02 males: 1 female; P < 0.001). Almost all recorded specimens were adult (98.1%). Mean straight carapace length (SCL) and body mass (BM) of adult turtles were: SCL = 128.65 mm, BM = 345 g for males (n = 168) and SCL = 135.37 mm, BM = 463 g for females (n = 83).
