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 †Symmetrodonta Simpson, 1925 - symmetrodonts see Infraclass Symmetrodonta Simpson, 1925
             Order †Spalacotherioidea Prothero, 1981 see Order Spalacotheriida Prothero, 1981
               Family †Spalacotheriidae Marsh, 1887
                 1 Genus †Spalacotherium Owen, 1854
                 2 Genus †Spalacotheroides Patterson, 1955
                 3 Genus †Symmetrodontoides Fox, 1976
                 4 Genus †Spalacotheridium Cifelli, 1990
                 5 Genus †Microderson Sigogneau-Russell, 1991