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Öğe Chromosomal variation in social voles: a Robertsonian fusion in Gunther's vole(SPRINGER HEIDELBERG, 2013) Zima, Jan; Arslan, Atilla; Benda, Petr; Macholan, Milos; Krystufek, BorisThe study reports on chromosomes in several populations of social voles from south-eastern Europe and the Middle East. The standard karyotypes of individuals of Microtus hartingi and Microtus guentheri originating from both south-eastern Europe and Asia Minor comprised 54 mostly acrocentric chromosomes. However, variation between populations was found in the amount and distribution of C-heterochromatin in certain autosomes and the sex chromosomes. Furthermore, a specific pattern of argyrophilic nucleolar organizer region distribution was recorded in different geographic populations. In a population from Asia Minor, a heterozygous centric fusion of two autosomes was found. The G-banded karyotypes of M. guentheri and Microtus socialis were compared, and tandem fusions of autosomes were suggested as possible mechanism of the divergence. The karyotypes of the nine currently recognized species of social voles are reviewed, and implications of chromosomal data for systematics are evaluated.Öğe Evolutionary history of mole rats (genus Nannospalax) inferred from mitochondrial cytochrome b sequence(OXFORD UNIV PRESS, 2012) Krystufek, Boris; Ivanitskaya, Elena; Arslan, Atilla; Arslan, Emine; Buzan, Elena V.Mole rats (genus Nannospalax) display prolific chromosomal variation with more than 50 distinct cytotypes. These cytotypes are largely indistinguishable morphologically, are mainly allopatric and their taxonomic ranking is contradictory. We established a cytochrome b phylogeny for 15 cytotypes belonging to all three species recognized on morphological grounds (morphospecies): N. leucodon, N. xanthodon and N. ehrenbergi. Phylogenetic reconstructions yielded two highly divergent groups which are in agreement with the current division into two subgenera (Nannospalax and Mesospalax). The former comprised samples from south-eastern Turkey, Israel and Egypt (the morphospecies N. ehrenbergi). Basal dichotomy within Mesospalax remained unresolved and the putative sister position of N. leucodon against the two lineages of N. xanthodon was not supported in our analysis. Net divergences between sister cytotypes were low (< 2.0%) and two N. leucodon cytotypes were not even reciprocally monophyletic. Among the three morphospecies, the genetic diversity was lowest in N. leucodon (2.4% +/- 0.3%), highest in N. xanthodon (8.8% +/- 0.7%) and intermediate in N. ehrenbergi (5.0% +/- 0.5%). Our results show that associations between genetic and chromosomal variation are not widespread and common in mole rats, and therefore refute the generalization of a cytotype-equals-species approach. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 446455.Öğe Fossorial morphotype does not make a species in water voles(WALTER DE GRUYTER GMBH, 2015) Krystufek, Boris; Koren, Toni; Engelberger, Simon; Horvath, Gyozo F.; Purger, Jeno J.; Arslan, Atilla; Chisamera, GabrielPhenetic and ecological plasticity in Arvicola has caused a long-standing dispute over the number of species within the genus, which is currently thought to consist of two aquatic (sapidus, amphibius) and one fossorial species (scherman). We used mitochondrial cytochrome b (cytb) gene sequences to reconstruct phylogenetic relationships between the fossorial and the aquatic water voles from the various regions of their European and Asiatic range. These two types differed morphologically and exhibited allopatric ranges. Our study provided 50 new haplotypes, generating a total dataset of 70 different water vole cytb haplotypes. Phylogenetic reconstructions retrieved two major lineages that were in a sister position to A. sapidus: a fossorial Swiss lineage and a widespread cluster, which contained aquatic and fossorial water voles from Europe and western Siberia. The phylogeographic architecture in water voles is explained by Quaternary climatic dynamics. Our results show that A. scherman in its present scope is not a monophyletic taxon.Öğe Mitochondrial Divergence Between Three Cytotypes of the Anatolian Mole Rat, Nannospalax Xanthodon (Nordmann, 1840)(TAYLOR & FRANCIS LTD, 2010) Arslan, Emine; Gülbahçe, Elif; Arıkoğlu, Hilal; Arslan, Atilla; Buzan, Elena V.; Krystufek, BorisThe Blind Mole Rats of Anatolia (Nannospalax xanthodon (Nordmann, 1840)) are characterised by prolific chromosomal diversification. While the geographic distribution of various cytotypes is well documented, opinions on their taxonomic ranking varies amongst authorities. A partial sequence (630 bp) of mitochondria] cytochrome b gene in 13 Blind Mole Rats from the Konya basin, central Anatolia, which represented three distinct cytotypes (2n = 40, 58, and 60) yielded nine cyt b haplotypes. Phylogenetic reconstructions recognized three well supported lineages which matched diploid number counts. Genetic divergences between cytotypes were high (K2P between 8.16% +/- 1.19 and 11.33% +/- 1.42) and application of the 2% divergence rate to the net divergence estimates suggests their divergence about 3.84 and 5.43 Mya (95% confidence interval = 1.53-8.19 Mya). If one would rely on genetic operational criteria in species delimitation, there would be little doubt that the three Nannospalax cytotypes analysed in this study belong to distinct allopatric species. Before translating the results into formal taxonomy, more genetic information should be acquired on different Nannospalax cytotypes occupying the eastern Mediterranean.Öğe Mitochondrial sequences point on a cryptic species in five-toed jerboas, subgenus Paralactaga(WALTER DE GRUYTER GMBH, 2013) Krystufek, Boris; Arslan, Atilla; Shehab, Adwan; Abi-Said, Mounir R.; Zupan, Sara; Luznik, MartinaWe addressed the species taxonomy of five-toed jerboas (Allactaga, subgenus Paralactaga) in the Middle East by applying molecular markers (cytochrome b and a partial 16S rRNA). The study consisted of 17 specimens from eight localities in the Middle East, representing both species: Allactaga euphratica and Allactaga williamsi. The phylogenetic reconstructions yielded three highly divergent lineages, which failed to conform to the recent taxonomy of Paralactaga. The first lineage (williamsi lineage) encompassed all the samples of A. williamsi from Turkey and Iran and also the specimens of A. euphratica from Lebanon. The haplotypes of A. euphratica were arranged into two lineages, which showed strong geographic associations. One lineage contained samples from Harran in Turkey and from Iran, while all the samples from Syria clustered in another lineage. The pairwise Kimura two-parameter values suggested similar divergences between the three lineages and were within the range reported for a sister species of rodents. Our results point to a cryptic species in A. euphratica and also provide evidence of the expanded range of A. williamsi further south to Lebanon.Öğe Review of chromosome races in blind mole rats (Spalax and Nannospalax)(INST VERTEBRATE BIOLOGY AS CR, 2016) Arslan, Atilla; Krystufek, Boris; Matur, Ferhat; Zima, JanThe blind mole rats (Spalacinae) reveal fascinating chromosomal variation, resulting from complex karyotype re-arrangements. This variation occurs between species, between populations of single species (polytypy) and within populations (polymorphism). This article reviews the current knowledge on blind mole rats' karyotypes and their variation. A special attention is paid to differentiation of the karyotype within a species and the patterns of chromosomal variation, which result in evolution of distinct chromosomal races (cytotypes). The chromosome races are defined as a group of geographically contiguous or recently separated populations which share a similar chromosome complement by descent. The present review indicated the existence of 73 distinct chromosome races recorded in blind mole rats classified within the genus Nannospalax, along with the seven species recognized within the genus Spalax. In total, 12 distinct diploid numbers of chromosomes were reported (2n = 36-62); and variation in chromosome morphologies was observed between populations with the same number of chromosomes (NF = 62-124). The blind mole rats classified in the genus Spalax revealed rather uniform karyotype both between and within the recognized species. Considering the traditional species classified in the Nannospalax genus, 25 races can be distinguished within N. leucodon, 28 races within N. xanthodon and 20 races within N. ehrenbergi. Hybrids between the races are found only exceptionally and they seem to be almost absent in extensive areas (Europe, Turkey). This fact indicates that chromosomal evolution in blind mole rats may be related to speciation processes. The definitive phylogenetic and taxonomic conclusions can be derived only after application of reliable molecular markers and setting of estimates of genetic distances and gene flow between populations.Öğe Systematic relationships within the Microtus arvalis (Rodentia: Cricetidae) group in Iran, inferred from cytogenetic analyses(TAYLOR & FRANCIS LTD, 2018) Mahmoudi, Ahmad; Zima, Jan; Krystufek, Boris; Darvish, Jamshid; Aliabadian, Mansour; Arslan, AtillaThe distribution of C-heterochromatin and nucleolar organizer regions (NORs) was studied in three species of voles of the Microtus arvalis group in Iran: M. mystacinus, M. kermanensis, and M. transcaspicus. The C-banding pattern and NORs distribution were similar in M. mystacinus and M. kermanensis suggesting taxonomic proximity of these two species. At the same time, the karyotypes of M. mystacinus from Iran were different in C-banding pattern from the complements of conspecific 54-chromosome voles from Europe and other regions of Asia. The most distinct difference was in size of the distal C-positive block of heterochromatin on the X chromosome. In this respect M. mystacinus from Iran and M. kermanensis resembled M. transcaspicus. Small size of the distal C-positive heterochromatic block may be ancestral whereas larger size is derived. The X chromosome of M. transcaspicus can be derived from that of M. mystacinus and M. kermanensis by a large inversion or centromeric shift.Öğe Taxonomic identity of Chionomys nivalis spitzenbergerae (Mammalia: Rodentia)(TAYLOR & FRANCIS LTD, 2017) Arslan, Atilla; Arslan, Emine; Mahmoudi, Ahmad; Bannikova, Anna; Krystufek, BorisThe most genetically divergent populations of the European snow vole Chionomys nivalis occupy the extreme eastern range of the Black Sea and the Caspian Sea. It was recently suggested that subspecies C. n. spitzenbergerae from the Central Taurus Mountains (Turkey) represents a highly divergent lineage of C. nivalis from the Aladag Range which induced us to address its status by examining topotype specimens. Two females karyotyped displayed 54 mitotic chromosomes of 25 acrocentric autosomal pairs. One of the smallest autosomal pairs was heteromorphic in both specimens, consisting of a submetacentric and an acrocentric chromosomes (NFa = 53). Cytochrome b sequences however unambiguously clustered both individuals with reference sequences from C. nivalis from Turkey. We conclude that a deviant haplotype from the Aladag Range does not represent C. n. spitzenbergerae. Its taxonomic identity was not resolved in our study. Further attention should be devoted to snow voles from Central Anatolia and Western Iran, which are characterized by cranial peculiarities.