Mammaliaformes Rowe 1988
   [crown] Class Mammalia Linnaeus, 1758 - mammals
     Subclass Theriiformes Rowe, 1988 see Division Theriiformes Rowe, 1988
       Infraclass Holotheria Wible, Rougier, Novacek, McKenna & Dashzeveg, 1995 see Clade Holotheria Wible, Rougier, Novacek, McKenna & Dashzeveg 1995
         Superlegion Trechnotheria McKenna, 1975 see Clade Trechnotheria McKenna 1975
           Legion Cladotheria McKenna, 1975 see Clade Cladotheria McKenna 1975
             Sublegion Zatheria McKenna, 1975 see Clade Zatheria McKenna 1975
               Infralegion Tribosphenida McKenna, 1975 see Subclass Boreosphenida Luo, Cifelli & Kielan-Jaworowska, 2001
                 [crown] Supercohort Theria Parker & Haswell, 1897 - therians see Subclass Theria Parker & Haswell, 1897
                   Cohort Placentalia Owen, 1837 - placentals
                     Magnorder Epitheria McKenna, 1975 see Cohort Placentalia Owen, 1837
                       Superorder Preptotheria McKenna, 1975
                         Grandorder Anagalida Szalay & McKenna, 1971 see Order Anagalida Szalay & McKenna, 1971
                           Mirorder Simplicidentata Weber, 1904
                             Order Rodentia Bowdich, 1821 - rodents
                               Suborder Myomorpha Brandt, 1855 see Infraorder Myomorphi
                                 Infraorder Geomorpha Thaler, 1966 see Infraorder Castorimorphi
                                   Superfamily Geomyoidea Bonaparte, 1845
                                     Family Geomyidae Bonaparte, 1845 - pocket gophers
                                       Subfamily Heteromyinae Gray, 1868 - pocket mice, kangaroo rats, and kangaroo mice
                                         Tribe Perognathini Coues, 1875 - pocket mice see Subfamily Perognathinae Coues, 1875
                                           Genus †Oregonomys Martin, 1984