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In this study, we present an assessment of the evolutionary history and phylogenetic relationships of Asian mountain voles of the subgenus Aschizomys, genus Alticola, based on extensive sampling and phylogenetic analyses of data from mitochondrial and nuclear markers. Two species of this subgenus are widespread in the mountain areas of north-eastern Asia. However, both their distribution and taxonomic borders remained questionable for more than 100 years. Our study showed discordance in the phylogenetic patterns between nuclear and mtDNA markers. We found that mtDNA in A. lemminus is paraphyletic relative to A. macrotis, but nuclear markers demonstrated reciprocal monophyly. According to species distribution modeling, ranges of A. macrotis and A. lemminus experienced a secondary contact during the Last Glacial Maximum (approximately 22 kyr BP), and thus a hybridization event seems plausible during that period. Species tree analyses recovered a sister group relationship between the two species of the Aschizomys subgenus, with an estimated divergence date of around 0.8 Ma. Our results provided good support for currently recognized subspecies within both A. macrotis and A. lemminus based on mitochondrial and nuclear datasets. A new, yet undescribed form, supposedly of a subspecific status within A. lemminus, was found in the Bureinskiy Range in the Khabarovsk area. This finding expands the current species distribution range further to the southeast.

The current study evaluates the selection signals in the evolution of mitochondrial DNA of voles, subfamily Arvicolinae, during the colonization of subterranean environments. The comparative sequence analysis of mitochondrial protein-coding genes of eight subterranean vole species (Prometheomys schaposchnikowi, three species of the genus Ellobius: E. talpinus, E. fuscocapillus and E. lutescens, two species of the genus Terricola: T. subterraneus and T. daghestanicus, Lasiopodomys mandarinus and Hyperacrius fertilis) and their closest aboveground relatives using codon-substitution models was applied. The highest number of selection signatures was detected in genes ATP8 and CYTB. The relaxation of selection was observed in most mtDNA protein-coding genes. In mole voles (genus Ellobius) the signatures of adaptive evolution of mitochondrial genes related to subterranean niche were most pronounced. The number of selection signatures was found to be independent of the evolutionary age of the lineage but fits the degree of specialization to the subterranean niche. The common trends of selective pressures were observed among the evolutionary ancient and highly specialized subterranean rodent families and phylogenetically young lineages of voles. It suggests that the signatures of adaptations in individual mitochondrial protein-coding genes associated with the colonization of the subterranean niche may appear within a rather short evolutionary timespan.

The subterranean voles of the genus Ellobius are species of subfamily Arvicolinae well adapted to underground life. In this paper, we report the assemblies of complete mitochondrial genomes for thr...

The subterranean voles of the genus Ellobius are species of subfamily Arvicolinae well adapted to underground life. In this paper, we report the assemblies of complete mitochondrial genomes for three mole voles from genus Ellobius – northern mole vole Ellobius talpinus (16,376 bp), transcaucasian mole vole E. lutescens (16,540 bp), and southern mole vole E. fuscocapillus (16,388 bp). Each of three mitogenomes encode for 12S and 16S rRNAs, 22 tRNAs, 13 protein-coding genes, and D-loop in the characteristic arrangement of subfamily Arvicolinae (Rodentia: Cricetidae). This study verifies the evolutionary status of subgenera Bramus and Ellobius within the genus Ellobius at the molecular level. The mitochondrial genome would be a significant supplement for the Ellobius genetic background. The three Ellobius species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

The voles of the subgenus Microtus, which includes six species of the socalled “arvalis” group, have always been problematic for classification. Some group members differ in chromosome number and karyotype structure and yet appear morphologically indistinguishable, while others have very similar karyotypes despite exhibiting significant morphological differences. Two “arvalis” voles from Iran, M. kermanensis and M. mystacinus, are among the least studied members of this group. Here, we used cytochrome b sequences, morphological data and all other available material in an attempt to solve the mystacinuskermanensis taxonomie puzzle. The results of the phylogenetic analysis of the cytochrome b sequences showed that M. rossiaemeridionalis, M. mystacinus and M. kermanensis form a monophyletic group that is sister to M. arvalis. Within this group, M. mystacinus appears to be more dosely related to M. kermanensis than to M. rossiaemeridionalis; therefore, M. kermanensis may be considered the junior synonym of M. mystacinus. However, these two forms differed significantly in size and molar pattern. The attribution of M. kermanensis and M. rossiaemeridionalis to one species contradicts the preliminary results of experimental hybridisation and morphological data: they differ in size, qualitative dental features and baculum structure. The obtained data showed that until comprehensive analysis based on extensive sampling is available, it is expedient to retain the species names M. mystacinus, M. rossiaemeridionalis and M. kermanensis.

A method for obtaining 156, 155, 154m2, 154, 153Tb radiotracers by the irradiation of a europium oxide target of natural isotopic composition by 27 MeV α-particles is proposed. Terbium can be efficiently separated from bulk of europium by the reduction of the latter by zinc in an acidic solution and precipitation as EuSO4. The optimum Zn/Eu3+ and (NH4)2SO4/Eu3+ molar ratios are 20 and 3, respectively. Terbium is additionally purified from europium and gadolinium by extraction chromatography using LN Resin. It is demonstrated that optimum separation is attained in 0.6 M HNO3. The Tb/Eu separation coefficient was ~5·105. The yield of terbium was about 90%. Time of all steps was 1.5–2 h. The proposed procedure makes it possible to obtain no carrier added terbium radiotracers.

An analysis of the phylogenetic position of the Olkhon mountain vole (Alticolaolchonensis Litvinov 1960) using the sequences of four nuclear (BRCA, GHR, LCAT, and IRBP) and one mitochondrial (cyt. b) genes was undertaken. It was noted that, until recently, multiple studies of the systematic position of this vole had been based exclusively on morphological data, while the major taxonomic traits contained contradictory information regarding both the subgeneric status of this species and its genus. It was established that the molecular data and morphology data allow us to attribute the Lake Baikal vole unambiguously to the nominative subgenus Alticola instead of Aschizomys.