Microtus tatricus occurs in the Carpathian Mountains of Slovakia, Poland, Ukraine and Romania – a list of current distribution records is given. The species’ distribution range is insular on the scale of its entire distribution and fragmented within each mountain range inhabited. The overall altitudinal range is 650–2350 m a.s.l., with the largest number of collecting sites situated between 1100–1700 m a.s.l. The total range size of M. tatricus was estimated as 840 km2 and the total population size at between 200,000–250,000 individuals. A possible reduction in the species’ distribution range is discussed.
We present a phylogenetic analysis of snow voles by combining all published cytochrome b sequences of 47 species of Microtus, Blanfordimys, Neodon and Chionomys and a new sequence from Chionomys gud. By applying powerful, modern approaches to phylogenetic reconstruction such as maximum likelihood (ML) and Bayesian inference methods (BI), we provide new information on the relationships between Chionomys and Microtus. Both phylogenetic analysis methods showed that the genus Microtus is paraphyletic with respect to Blanfordimys, Neodon and Microtus gregalis. The BI topology recovered strong support for the monophyly of Chionomys + Microtus gregalis, while th monophyly of Chionomys was supported only by the ML analysis. The two Chionomys lineages (defined by molar morphology and karyological features), “nivalis” (C. nivalis) and “roberti” (C. gud and C. roberti), were strongly supported by cytochrome b analysis.