Phylogeographic Structure of Alexandromys maximowiczii Schrenck, 1859 (Rodentia, Cricetidae): A Comparison of the mtDNA Control Region Variability and Chromosome Polymorphism Data

Abstract

Genetic structure of the Maximowicz’s vole Alexandromys maximowiczii was assessed using data on the mtDNA control region variability, and the high level of genetic variability was revealed for the species as a whole. Three phylogenetic groups (“east,” “west,” and “south”) were distinguished, and within the “east” group, three subclades (“Chit,” “Amur,” and “Khab”) were identified. All phylogenetic groups and subclades were characterized by mainly allopatric geographical distribution across the species range with one “hybrid” sampling found in the vicinity of the settlement of Savvo-Borzya (Zabaykalsky krai), the individuals of which had different variants of the mt genotype. One individual carried the “west” variant, and the second one—the “east”/“Amur” variant. The revealed phylogeographic structure was generally congruent with the differentiation pattern as revealed by the chromosomal forms, but did not agree with the previously accepted subspecies system. Complex intraspecific subdivision of the Maximowicz’s vole, revealed at different organization levels (molecular genetic, as well as chromosomal), reflects not only complex geography of the study area, but also the history of dynamic changes in the natural environment.