Class Mammalia Linnaeus, 1758 - mammals
   Order Rodentia Bowdich, 1821 - rodents
     Suborder Sciurognathi (Tullberg, 1899) see Suborder Sciuromorpha Brandt, 1855
       Family Muridae Batsch, 1788 - rats, mice, hamsters, voles, lemmings, and gerbils
         Subfamily Arvicolinae Gray, 1821 - voles
           Genus Microtus Schrank, 1798 - voles
             Subgenus Terricola Fatio, 1867
               1 Microtus subterraneus species group
               2 Microtus duodecimcostatus species group
               3 Microtus savii species group
               6 Microtus schelkovnikovi species group