Class Mammalia Linnaeus, 1758 - mammals
   Subclass Theria Parker & Haswell, 1897
     Order Soricomorpha Gregory, 1910 see Suborder Soricomorpha Gregory, 1910
       Family Soricidae Fischer, 1814 - shrews
         Subfamily Soricinae Fischer, 1814
           Tribe Soricini Fischer, 1814
             Genus Sorex Linnaeus, 1758 - long-tailed shrews
               Subgenus Otisorex De Kay, 1842
                 Sorex vagrans complex
                   Sorex palustris Richardson, 1828 - American water shrew
                     Sorex palustris hydrobadistes Jackson, 1926