RESUMO
Cryptic diversity poses a great obstacle in our attempts to assess the current biodiversity crisis and may hamper conservation efforts. The gekkonid genus Mediodactylus, a well-known case of hidden species and genetic diversity, has been taxonomically reclassified several times during the last decade. Focusing on the Mediterranean populations, a recent study within the M. kotschyi species complex using classic mtDNA/nuDNA markers suggested the existence of five distinct species, some being endemic and some possibly threatened, yet their relationships have not been fully resolved. Here, we generated genome-wide SNPs (using ddRADseq) and applied molecular species delimitation approaches and population genomic analyses to further disentangle these relationships. Τhe most extensive nuclear dataset, so far, encompassing 2,360 loci and â¼ 699,000 bp from across the genome of Mediodactylus gecko, enabled us to resolve previously obscure phylogenetic relationships among the five, recently elevated, Mediodactylus species and to support the hypothesis that the taxon includes several new, undescribed species. Population genomic analyses within each of the proposed species showed strong genetic structure and high levels of genetic differentiation among populations.
Assuntos
Lagartos , Filogenia , Filogeografia , Animais , Região do Mediterrâneo , Lagartos/genética , Lagartos/classificação , Polimorfismo de Nucleotídeo Único , Variação Genética , Genética Populacional , DNA Mitocondrial/genética , Análise de Sequência de DNARESUMO
Mountains play a key role in forming biodiversity by acting both as barriers to gene flow among populations and as corridors for the migration of populations adapted to the conditions prevailing at high elevations. The Anatolian and the Zagros Mountains are located in the Alpine-Himalayan belt. The formation of these mountains has influenced the distribution and isolation of the animal population since the late Cenozoic. Apathya is a genus of lacertid lizards distributed along these mountains with two species, i.e., Apathya cappadocica and Apathya yassujica. The taxonomy status of lineages within the genus is complicated. In this study, we tried to collect extensive samples from throughout the distribution range, especially within the Zagros Mountains. Also, we used five genetic markers, two mitochondrial (COI and Cyt b) and three nuclear (C-mos, NKTR, and MCIR), to resolve the phylogenetic relationships within the genus and explain several possible scenarios that shaped multiple genetic structures. The combination of results in the current study indicated eight well-support monophyletic lineages that separated to two main groups; group 1 including A. c. cappadocica, A. c. muhtari and A. c. wolteri, group 2 contains four regional clades Turkey, Urmia, Baneh and Ilam, and finally a single clade belonging to the species A. yassujica. In contrast to previous studies, Apathya cappadocica urmiana was divided into four clades and three clades were recognized within Iranian boundaries. The clades have dispersed from Anatolia to adjacent regions in the south of Anatolia and the western Zagros Mountains. According to the evidence generated in this study this clade is paraphyletic. Based on our assumption, orogeny activities and also climate fluctuations in Middle Miocene and Pleistocene have influenced to formation of lineages. In this study we revisit the taxonomy of the genus and demonstrate that the species diversity was substantially underestimated. Our findings suggest that each of the eight clades corresponding to subspecies and distinct geographic regions deserve to be promoted to species level.
Assuntos
Lagartos , Animais , Filogenia , Lagartos/genética , Irã (Geográfico) , DNA Mitocondrial/genética , Evolução Biológica , Variação GenéticaRESUMO
Microplastics (MPs), which are of increasing concern in almost all ecosystems, continue to be an environmental threat. In the present study, the presence of MPs is investigated by using the gastrointestinal tracts (GITs) obtained from the true frog individuals sampled in the past years. The sample consists of a total of 146 individuals obtained from various regions of Türkiye. The results show that MPs were found in 87 adult frog individuals. The most predominant shape of MPs found was fiber, with a predominance of transparent color, and ethylene-vinyl acetate (EVA) was also the most abundant microplastic material. The highest amount of MPs among adult frog populations were found in the Denizli province. The size of MPs ranged between a minimum of 66 and a maximum of 3770 µm. In addition, no relationship was found between the body length and weight of the frogs and the sizes of MPs. Historically, most MPs were found in samples from 1990 and the highest content in terms of both color and material was detected in 1990. MPs were detected in almost all the years studied, but microplastic abundance varied from year to year. These results can be explained by the number of samples, habitat, and feeding behavior of adult frogs.
Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Animais , Plásticos , Ecossistema , Ranidae , Monitoramento Ambiental , Poluentes Químicos da Água/análiseRESUMO
As body size strongly determines the biology of an organism at all levels, it can be expected that miniaturization comes with substantial structural and functional constraints. Dwarf snakes of the genus Eirenis are derived from big, surface-dwelling ancestors, considered to be similar to those of the sister genus Dolichophis. To better understand the structural implications of miniaturization on the feeding apparatus in Eirenis, the morphology of the cranial musculoskeletal system of Dolichophis schmidti was compared with that of the miniature Eirenis punctatolineatus and E. persicus using high-resolution µCT data. The gape index was compared between D. schmidti and 14 Eirenis species. Our results show a relatively increased neurocranium size and decreased maximal jaw muscle force in E. persicus, compared with the D. schmidti, and an intermediate situation in E. punctatolineatus. A significant negative allometry in gape index relative to body size is observed across the transition from the Dolichophis to Pediophis and Eirenis subgenera. However, the gape index relative to head size showed a significant negative allometry only across the transition from the Dolichophis to Pseudocyclophis subgenus. In Dolichophis-Eirenis dwarfing lineages, different structural patterns are observed through miniaturization, indicating that overcoming the challenge of miniaturization has achieved via different adaptations.
Assuntos
Tamanho Corporal/fisiologia , Crânio/anatomia & histologia , Serpentes/anatomia & histologia , Animais , Comportamento Alimentar/fisiologiaRESUMO
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.
Assuntos
Genótipo , Lagartos , Partenogênese , Alelos , Animais , Variação Genética , Lagartos/genética , Repetições de MicrossatélitesRESUMO
Cryptic phylogeographic diversifications provide unique models to examine the role of phylogenetic divergence on the evolution of reproductive isolation, without extrinsic factors such as ecological and behavioural differentiation. Yet, to date very few comparative studies have been attempted within such radiations. Here, we characterize a new speciation continuum in a group of widespread Eurasian amphibians, the Pelobates spadefoot toads, by conducting multilocus (restriction site associated DNA sequencing and mitochondrial DNA) phylogenetic, phylogeographic and hybrid zone analyses. Within the P. syriacus complex, we discovered species-level cryptic divergences (>5 million years ago [My]) between populations distributed in the Near-East (hereafter P. syriacus sensu stricto [s.s.]) and southeastern Europe (hereafter P. balcanicus), each featuring deep intraspecific lineages. Altogether, we could scale hybridizability to divergence time along six different stages, spanning from sympatry without gene flow (P. fuscus and P. balcanicus, >10 My), parapatry with highly restricted hybridization (P. balcanicus and P. syriacus s.s., >5 My), narrow hybrid zones (~15 km) consistent with partial reproductive isolation (P. fuscus and P. vespertinus, ~3 My), to extensive admixture between Pleistocene and refugial lineages (≤2 My). This full spectrum empirically supports a gradual build up of reproductive barriers through time, reversible up until a threshold that we estimate at ~3 My. Hence, cryptic phylogeographic lineages may fade away or become reproductively isolated species simply depending on the time they persist in allopatry, and without definite ecomorphological divergence.
Assuntos
Anuros/classificação , Especiação Genética , Genética Populacional , Isolamento Reprodutivo , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Europa (Continente) , Fluxo Gênico , Hibridização Genética , Oriente Médio , Filogenia , Filogeografia , Análise de Sequência de DNA , SimpatriaRESUMO
Kotschy's Gecko, Mediodactylus kotschyi, is a small gecko native to southeastern Europe and the Levant. It displays great morphological variation with a large number of morphologically recognized subspecies. However, it has been suggested that it constitutes a species complex of several yet unrecognized species. In this study, we used multilocus sequence data (three mitochondrial and three nuclear gene fragments) to estimate the phylogenetic relationships of 174 specimens from 129 sampling localities, covering a substantial part of the distribution range of the species. Our results revealed high genetic diversity of M. kotschyi populations and contributed to our knowledge about the phylogenetic relationships and the estimation of the divergence times between them. Diversification within M. kotschyi began approximately 15 million years ago (Mya) in the Middle Miocene, whereas the diversification within most of the major clades have been occurred in the last 5â¯Mya. Species delimitation analysis suggests there exists five species within the complex, and we propose to tentatively recognize the following taxa as full species: M. kotschyi (mainland Balkans, most of Aegean islands, and Italy), M. orientalis (Levant, Cyprus, southern Anatolia, and south-eastern Aegean islands), M. danilewskii (Black Sea region and south-western Anatolia), M. bartoni (Crete), and M. oertzeni (southern Dodecanese Islands). This newly recognized diversity underlines the complex biogeographical history of the Eastern Mediterranean region.
Assuntos
Loci Gênicos , Variação Genética , Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Geografia , RNA Ribossômico 16S/genética , Alinhamento de Sequência , Especificidade da Espécie , Fatores de TempoRESUMO
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 200-70kyr 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.
Assuntos
Lagartos/genética , Partenogênese/genética , Animais , Área Sob a Curva , Citocromos b/classificação , Citocromos b/genética , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Haplótipos , História Antiga , Hibridização Genética , Lagartos/classificação , Lagartos/metabolismo , NADH Desidrogenase/classificação , NADH Desidrogenase/genética , Filogenia , Filogeografia/história , Curva ROCRESUMO
Morphological and DNA data support that the East Mediterranean snake-eyed skink Ablepharus kitaibelii represents a species complex that includes four species A. kitaibelii, A. budaki, A. chernovi, and A. rueppellii, highlighting the need of its taxonomic reevaluation. Here, we used Bayesian and Maximum Likelihood methods to estimate the phylogenetic relationships of all members of the complex based on two mitochondrial (cyt b, 16S rRNA) and two nuclear markers (MC1R, and NKTR) and using Chalcides, Eumeces, and Eutropis as outgroups. The biogeographic history of the complex was also investigated through the application of several phylogeographic (BEAST) and biogeographic (BBM) analyses. Paleogeographic and paleoclimatic data were used to support the inferred phylogeographic patterns. The A. kitaibelli species complex exhibits high genetic diversity, revealing cases of hidden diversity and cases of non-monophyletic species such as A. kitaibelii and A. budaki. Our results indicate that A. pannonicus branches off first and a group that comprises specimens of A. kitaibelli and A. budaki from Kastelorizo Island group (southeast Greece) and southwest Turkey, respectively is differentiated from the rest A. kitaibelli and A. budaki populations and may represent a new species. The estimated divergence times place the origin of the complex in the Middle Miocene (â¼16Mya) and the divergence of most currently recognized species in the Late Miocene. The inferred ancestral distribution suggests that the complex originated in Anatolia, supposing that several vicariance and dispersal events that are related with the formation of the Mid-Aegean Trench, the Anatolian Diagonal and the orogenesis of the mountain chains in southern and eastern Anatolia have led to current distribution pattern of A. kitaibelii species complex in the Balkans and Middle East.
Assuntos
Lagartos/classificação , Animais , Península Balcânica , Teorema de Bayes , Citocromos b/classificação , Citocromos b/genética , Citocromos b/metabolismo , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Variação Genética , Grécia , Funções Verossimilhança , Lagartos/genética , Filogenia , Filogeografia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Receptor Tipo 1 de Melanocortina/classificação , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 1 de Melanocortina/metabolismo , Receptores Imunológicos/classificação , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , TurquiaRESUMO
Apathya is a lacertid genus occurring mainly in south-east Turkey and its adjacent regions (part of Iran and Iraq). So far two morphological species have been attributed to the genus; A. cappadocica (with five subspecies, A. c.cappadocica, A. c.muhtari, A. c.schmidtlerorum, A. c. urmiana and A. c.wolteri) and A.yassujica. The first species occupies most of the genus' distribution range, while A. yassujica is endemic of the Zagros Mountains. Here, we explored Apathya's taxonomy and investigated the evolutionary history of the species by employing phylogenetic and phylogeographic approaches and using both mitochondrial (mtDNA) and nuclear markers. The phylogenetic relationships and the genetic distances retrieved, revealed that Apathya is a highly variable genus, which parallels its high morphological variation. Such levels of morphological and genetic differentiation often exceed those between species of other Lacertini genera that are already treated as full species, suggesting the necessity for a taxonomic revision of Apathya. The phylogeographical scenario emerging from the genetic data suggests that the present distribution of the genus was determined by a combination of dispersal and vicariance events between Anatolia and Southwest Asia dating back to the Miocene and continuing up to the Pleistocene. Key geological events for the understanding of the phylogeography of the genus are the movement of the Arabian plate that led to the configuration of Middle East (orogenesis of the mountain ranges of Turkey and Iran) and the formation of Anatolian Diagonal.
Assuntos
Distribuição Animal , Variação Genética , Fenômenos Geológicos , Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , DNA Mitocondrial/genética , Irã (Geográfico) , Funções Verossimilhança , Região do Mediterrâneo , Modelos Genéticos , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNARESUMO
A broad sample of Darevskia rudis from the main part of its range was reviewed with regard to external morphology (discriminant, UPGMA, MST and ANOVA analyses) and osteology. Darevskia bithynica is raised to species rank, with two subspecies: D. b. bithynica and D. b. tristis. The other subspecies are fairly similar (D. r. rudis being the most different). Two singular populations are described as subspecies: D. r. mirabilis ssp. nov. from Kaçkar Mountains, geographically adjoins the otherwise different D. r. bischoffi and D. r. bolkardaghica ssp. nov., which is geographically isolated but that seems to be very closely related to D. r. obscura.
Assuntos
Osso e Ossos/anatomia & histologia , Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Feminino , Masculino , Filogenia , Especificidade da Espécie , TurquiaRESUMO
Six species belonging to the genus Lacerta live in Türkiye. In this study, both present and future potential distribution maps were created based on occurrence data and climatic variables for these six species. Two scenarios for future projections (shared socioeconomic pathways, SSPs,: 245 and 585) and two timeframes (2041-2060 and 2081-2100) were used. The present and future potential distributions of these species were compared. As a result, it was predicted that the distribution ranges in the six species will expand in the future, and this expansion has revealed new environments.
Assuntos
Mudança Climática , Ecossistema , PrevisõesRESUMO
A description of the skeletal development of ranids is scarce despite being well known in the family Ranidae. Herein, the description of several species of two genera representing the family Ranidae from Turkey is studied wherein the larval and adult cranial skeletons of Pelophylax caralitanus are described and compared with that of the water frog (Pelophylax bedriagae) and mountain frog (Rana macrocnemis). The data are based on cleared and double-stained specimens of 20 Gosner developmental Stages (26-46). The first element to ossify in P. caralitanus is the parasphenoid (Stage 30), followed by the exoccipitals (Stage 34) and prootics (Stage 35). The metamorphic climax commences at Stage 42 during which several modifications to the chondrocranium will unfold. In addition, ranids demonstrate remarkable differences between the water (Pelophylax sp.) and mountain (Rana sp.) frog species: (a) the ventromedial bridge between the corpora of the suprarostral cartilage in the larval upper jaw, (b) the number of processes of the central corpus in the hyobranchial skeleton, and (c) the differences in the ossification time and sequence between Pelophylax sp. and Rana sp. A detailed description of the larval osteological features of P. caralitanus conforms to the current phylogenetic position and provides a model for comparison with other ranids.
Assuntos
Osteogênese , Crânio , Animais , Filogenia , Cartilagem , Ranidae , LarvaRESUMO
Revealing biodiversity allows the accurate determination of the underlying causes of many biological processes such as speciation and hybridization. These processes contain many complex patterns, especially in areas with high species diversity. As two of the prominent zoogeographic areas, Anatolia and Caucasus are also home to the genus Darevskia, which has a complex morphological structure and parthenogenetic speciation. Darevskia valentini and D. rudis are two largely distributed taxa of this genus, both of which have a controversial taxonomic delimitation. Here we performed both a highly detailed morphological comparison and a molecular evaluation for the populations in both species groups. The most comprehensive taxonomic revision of this complex was carried out to determine the cases where the data obtained were compatible or not with each approach. As a result of the obtained outputs, it seems that D. spitzenbergerae stat. nov., D. mirabilis stat. nov. and D. obscura stat. nov. should be accepted as the species level, this later with subspecies D. o. bischoffi comb. nov. and D. o. macromaculata comb. nov.. Also, we propose two new taxa: D. josefschmidtleri sp. nov. and D. spitzenbergerae wernermayeri ssp. nov.. It has also been shown that "lantzicyreni" subspecies belong to D. rudis instead of D. valentini. The extensive revision has contributed to subsequent studies to more accurately understand the past histories of species in the genus Darevskia.
Assuntos
Lagartos , Animais , Lagartos/classificação , Lagartos/genética , Filogenia , Ásia Ocidental , Distribuição AnimalRESUMO
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, they suggest that some lineages possess specific properties that underpin successful parthenogenetic reproduction.
Assuntos
Lagartos , Animais , Evolução Biológica , Hibridização Genética , Lagartos/genética , Partenogênese/genética , FilogeniaRESUMO
All the Turkish populations studied, both those previously assigned to D. dryada (Subasi and Yoldere villages, near Hopa) and those attributed to D. clarkorum (the largest sample studied so far, 177 specimens in total), are indistinguishable from each other and therefore must all be ascribed to the natural variability of a monotypic D. clarkorum. The Georgian specimens from the Type Locality of D. dryada (Charnaly river gorge, Chevachauri district) are clearly different, so that taxon cannot be considered a simple synonym for D. clarkorum, but as a valid taxon, although its proper status (more probably as a subspecies of D. clarkorum), is yet to be clarified. It is a highly threatened population, so studies should be done in vivo or with as low intrusiveness as possible. Darevskia dryada is clearly larger (SVL) than any D. clarkorum studied, with strongly longer heads and pilei in adult males (and hence more teeth in dentary bone), and higher dorsalia counts. There also seem to be (but need to be studied in a larger sample) more longitudinal rows of temporal scales between tympanic and parietal plates, a tendency to have more supralabial scales; comparatively smaller values for longitudinal rows of scales on the ventral surface of the thigh between the femoral pores and the outer row of enlarged scales, and higher collaria, and circumanalia scales. Other differences in femoralia and gularia are also reflected in Darevsky Tuniyev's (1997) tables and should also be investigated with more Georgian specimens. Two supposed discriminant characters, the frontonasal index and the presence of developed masseteric, are not valid. The frontonasal index does not discriminate both taxa; D dryada specimens fall inside the variation of D. clarkorum for this character. Also the presence of a developed masseteric plate is supposed to be rare if at all in D. clarkorum but always present in D. dryada; however, it appears in nearly 75% of D. clarkorum studied and in all D. dyada, so is also no longer valid for taxa discrimination. Although very similar, D. clarkorum and D. dryada are morphologically different, and genetic studies (as the unpublished results mentioned by Fu, 1999) do not make the provenance of the specimens clear, and hence the correct identification of the supposed specimens of D. dryada used. There are no geographical clines in D. clarkorum. However, as stated by Schmidtler et al. (2002), there is an inverse relationship between altitude and dorsalia values in D. clarkorum. Both the general differentiation between populations and the scalation (dorsalia) appear statistically correlated with the altitude and also with latitude (being both factors not strictly the same). The correlation seems to be stronger with morphology in general (multiple scalation characters and head biometry) than only with dorsalia. In the case of the general differentiation among samples, it is also significantly correlated with temperatures during the activity period (April-September) and with precipitation during incubation (July-August). As these climatic parameters of temperature and precipitation are not directly correlated with the dorsalia variation, the relation with altitude (and perhaps latitude) must be linked to some other climatic parameter not studied here, perhaps solar radiation or evapotranspiration.
Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Meio Ambiente , Geografia , Masculino , TurquiaRESUMO
According to a large morphological dataset of specimens from Turkey to Iran and based on several morphological analyses, the Iranian populations of the skink Heremites vittatus are separated from other populations of this taxon in Turkey. The values of most of morphological characters were higher in the Turkish populations. Morphological variation among populations of H. vittatus (Olivier, 1804) from Turkey and the western slopes of the Zagros Mountains in Kermanshah province in Iran may be the result of different dispersal and vicariance events. Comparison the current study dataset with specimens from Egypt can definite the taxonomic status of Iranian and Turkish populations.
Assuntos
Lagartos , Animais , Variação Biológica da População , Irã (Geográfico) , Filogenia , TurquiaRESUMO
BACKGROUND: The rat snake genus Elaphe once comprised several dozens of species distributed in temperate through tropical zones of the New and Old World. Based on molecular-genetic analyses in early 2000s, the genus was split into several separate genera, leaving only 15 Palearctic and Oriental species as its members. One of the three species also occurring in Europe is Elaphe sauromates, a robust snake from the Balkans, Anatolia, Caucasus, Ponto-Caspian steppes, and Levant that has been suspected to be composed of two or more genetically diverse populations. Here, we studied the genetic structure and morphological variation of E. sauromates, aiming to better understand its inter-population relationships and biogeography, and subsequently revise its taxonomy. METHODS: We reconstructed the phylogeography and analyzed the genetic structure of E. sauromates populations originating from most of its geographic range using both mitochondrial (COI, ND4) and nuclear (C-MOS, MC1R, PRLR, RAG1) DNA gene fragments. We employed Maximum likelihood and Bayesian inference methods for the phylogenetic tree reconstructions, supplemented with species delimitation methods, analysis of haplotype networks, and calculation of uncorrected p-distances. Morphological variation in 15 metric and 18 meristic characters was studied using parametric univariate tests as well as multivariate general linearized models. In total, we analyzed sequences originating from 63 specimens and morphological data from 95 specimens of E. sauromates sensu lato. RESULTS: The molecular phylogeny identified two clearly divergent sister lineages within E. sauromates, with both forming a lineage sister to E. quatuorlineata. The genetic distance between them (5.80-8.24% in mtDNA) is similar to the distances among several other species of the genus Elaphe. Both lineages are also moderately morphologically differentiated and, while none of the characters are exclusively diagnostic, their combination can be used for confident lineage identification. Here, following the criteria of genetic and evolutionary species concepts, we describe the lineage from eastern Anatolia and parts of the Lesser and Great Caucasus as a new species E. urartica sp. nov. DISCUSSION: Elaphe urartica sp. nov. represents a cryptic species whose ancestors presumably diverged from their common ancestor with E. sauromates around the Miocene-Pliocene boundary. The intraspecific genetic structure indicates that the recent diversity of both species has been predominantly shaped by Pleistocene climatic oscillations, with glacial refugia mainly located in the Balkans, Crimea, and/or Anatolia in E. sauromates and Anatolia and/or the Caucasus in E. urartica sp. nov.
RESUMO
The intraspecific variability of Darevskia parvula (which has two classical subspecies easily identifiable by external characteristics, D. p. parvula and D. p. adjarica), was studied using various approaches including morphology (scalation and biometry), multivariate analyses (PCA, CDA, ANOSIM, UPGMA and MST), osteology, and molecular techniques. High mitochondrial distance, differences at the nuclear level and morphological distinctiveness warrant the specific status of both taxa, Darevskia parvula (Lantz Cyrén, 1913) and Darevskia adjarica (Darevsky Eiselt, 1980) stat. nov. A lectotype for D. parvula, originally described with syntypes of both species -D. parvula and D. adjarica- is designated. The uncorrected genetic distance between D. parvula and D. adjarica in the cytochrome b mitochondrial gene is 14.4% ± 1.9%. Intraspecific variability within D. parvula is very small (1.5% ± 0.5%), and was not detected in our samples of D. adjarica. The two species further differ by two mutations in the nuclear melano-cortin 1 receptor (mc1r) gene. Interestingly, past introgression of D. parvula mitochondrial haplotypes (5% ± 1% different to those currently known) into some D. adjarica has been detected in one locality; all the studied specimens of D. adjarica with mtDNA of D. parvula are unmistakably D. adjarica at the morphological and nuclear levels.Morphologically, there is almost no overlap between D. parvula and D. adjarica. These results are corroborated by CDA, MST and UPGMA trees. Specimens of the inland high mountain population of Ardahan (clearly D. adjarica in CDA, MST and UPGMA trees) occupy a somewhat intermediate position between both taxa in the PCA (when specimens and not populations as a whole are considered), but this morphological closeness may be attributed to the influence of climatic factors (continental conditions) on scalation of the specimens. Males appear to be more differentiated than females. Overlap among samples within each species is very marked; none can be separated clearly from its conspecifics. This is even more marked in D. parvula, which has a fairly small area compared to D. adjarica.Darevskia parvula and D. adjarica samples appear to be homogeneously clustered within species and well separated between the two species in the UPGMA trees. In males and females all the D. parvula samples are very similar and moderately differentiated. In males of D. adjarica, the most differentiated seems to be adjBorçka, the others all being clustered together, with adjÇaykara showing slightly more differentiation from the rest (adjOrtacalar, adjArdahan, adjIkizdere and adjÇermik).Darevskia adjarica females are also similarly distributed into two subgroups, one including Borçka, Çermik and Ardahan and the other including Ortacalar, Ikizdere and Çaykara. In both sexes, the inland Ardahan sample clearly belongs to D. adjarica.From the most connected MST samples, speculations can be made about areas of origin and expansion of the different taxa. Ortacalar (D. adjarica) and Hatila (D. parvula) are the most connected (morphologically more "central" in both taxa); in fact, both populations are relatively close, living on the northern (Black Sea) and southern (Anatolian) facing slopes, respectively of the Dogu Karadeniz Mountains (Kaçkar Mountains). This highlights these mountains, which rise from sea level up to nearly 4000 m asl. and have wide buffering possibilities against climate changes, as a zone of refuge and posterior dispersion of this species, and even of the original splitting into two taxa adapted to these different conditions, D. adjarica on the coast and D. parvula on the continental slope.Osteologically D. parvula and D. adjarica are very similar, although Georgian specimens from an isolated population (Atskuri) have closed clavicles not found in Turkish D. adjarica. Also, inland Ardahan D. adjarica have an extra vertebra in both males and females, compared to the other studied specimens from both species.The present study indicates that the situation in Turkey is that D. parvula is well differentiated and lives around the Çoruh River Valley, contoured by D. adjarica populations on the coastal-facing slopes of the Dogu Karadeniz Mountains on one side, and the Yalnizçam Mountains on the other side, where D. adjarica enters from Georgia as the opposite extreme of a geographic distribution. The attribution of more inland ranges to D. parvula or D. adjarica, as well as the detailed genetic structure of both taxa may be confirmed with more specific studies.
Assuntos
Lagartos , Filogenia , Animais , Mar Negro , Feminino , Georgia , República da Geórgia , Masculino , Osteologia , TurquiaRESUMO
Eggs, hatchlings, and adult loggerhead turtles, and incubation durations of clutches, were measured on three Turkish beaches (Dalyan, Fethiye and Göksu Delta), and some physical features of nests were compared. These features were not statistically different among the beaches, except for nest depth and distance to the high water mark. There was a positive relationship between hatchling mass and egg size. The carapace length of hatchlings was correlated with both egg diameter and incubation duration. The duration of asynchronous emergence of hatchlings on Fethiye beach was slightly longer than on the other two beaches, and the size of hatchlings decreased as asynchronous emergence proceeded. Of the hatchlings that emerged first, those that died were significantly smaller in SCL and mass than those that lived. These results suggest that smaller hatchlings may not be vigorous enough to emerge earlier from nests, and that they may be less fit.