Clade Mammaliaformes Rowe 1988 [Rowe 1988]
   [crown] Class Mammalia Linnaeus, 1758 - mammals
     Subclass Theriiformes (Rowe, 1988) M.C. McKenna & S.K. Bell, 1997 see Division Theriiformes
       Infraclass Holotheria (Wible et al., 1995) M.C. McKenna & S.K. Bell, 1997 see [unranked] Holotheria
         Superlegion Trechnotheria McKenna, 1975 see [unranked] Trechnotheria McKenna, 1975
           Legion Cladotheria McKenna, 1975 see [unranked] Cladotheria McKenna, 1975
             Sublegion Zatheria McKenna, 1975 see [unranked] Zatheria McKenna, 1975
               Infralegion Tribosphenida McKenna, 1975 see Sublegion Boreosphenida
                 Supercohort Theria (Parker & Haswell, 1897) M.C. McKenna & S.K. Bell, 1997 - therians see [unranked] Theria
                   Cohort Placentalia (Owen, 1837) M.C. McKenna & S.K. Bell, 1997 - placentals
                     Magnorder Epitheria (McKenna, 1975) M.C. McKenna & S.K. Bell, 1997 see Cohort Placentalia (Owen, 1837) M.C. McKenna & S.K. Bell, 1997
                       Superorder Preptotheria (McKenna, 1975) McKenna, 1993
                         Grandorder Ungulata Linnaeus, 1766
                           Mirorder Eparctocyona McKenna, 1975
                             Order †Arctostylopida Cifelli et al., 1989
                               Family †Arctostylopidae Schlosser, 1923
                                 1 Genus †Allostylops Zheng, 1979
                                 2 Subfamily †Arctostylopinae (Schlosser, 1923) Zheng, 1979
                                 3 Subfamily †Asiostylopinae Zheng, 1979