Living on the margin – phylogenetic assessment of the relict population of the forest dormouse (Dryomys nitedula) from Dzungarian Gobi, Mongolia. Living on the margin – phylogenetic assessment of the relict population of the forest dormouse (Dryomys nitedula) from Dzungarian Gobi, Mongolia

The forest dormouse Dryomys nitedula is distributed from Central Europe to SW Mongolia (91° E). Such an extensive but discontinuous distribution seems to have caused a deep diversification of its individual populations. In this study we provide the first genetic data (mitochondrial cyt b and nuclear IRBP) for Mongolian populations of D. n. angelus. To evaluate the current diversity of Dryomys we compared all populations of Dryomys nitedula that been studied until now. Our results show that the investigated populations of D. nitedula arise from three evolutionarily distinct lineages: the European, Caucasian, and Mongolian, the last of which represents a deeply divergent sister group of the W Palearctic populations. This division is also supported by species delimitation analyses. The genetic distances of cyt b between Mongolian and W Palearctic populations are approximately 11%, which corresponds to a divergence of 14 My old. These results indicate that the Mongolian lineage of D. nitedula is an independent evolutionary unit and can be considered as a separate species: Dryomys angelus Thomas, 1906.