Comparative phylogeography of the five Greek vole species infers the existence of multiple South Balkan subrefugia

Abstract

Despite extensive phylogenetic studies in the genus Microtus, several of its species have not been thoroughly evaluated. The present study focuses on a cytb molecular analysis of five vole species occurring in the southern Balkan Peninsula (M. felteni, M. thomasi, M. subterraneus, M. levis and M. guentheri), aiming to demonstrate the importance of thorough intraspecific sampling when the phylogeny of closely related taxa is tested. As a result, the Balkan populations of these voles showed significant intraspecific variation that distinguishes them from other European and Asian conspecifics and in some cases reveals distinct lineages even within the Balkan region. Their complex phylogeography suggest the existence of multiple subrefugia, located within the southern Balkan region, which promoted diversification of these voles during the Middle and Late Pleistocene glacial periods. The significant role of the southern Balkan Peninsula's paleogeographical and paleoclimatical characteristics in these small mammals' evolution is discussed.