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 Ferae (Linnaeus, 1758) McKenna, 1975 see Superorder Ferae (Linnaeus, 1758) Simpson, 1945
                           Order Carnivora Bowdich, 1821 - carnivores
                             Suborder Caniformia Kretzoi, 1943
                               Infraorder Arctoidea Flower, 1869
                                 Parvorder Ursida Tedford, 1976
                                   Superfamily Phocoidea (Gray, 1821) Smirnov, 1908
                                     Family Phocidae Gray, 1821 - true seals
                                       Subfamily Phocinae (Gray, 1821) Gill, 1866 - true seals, earless seals, hair seals
                                         Tribe Monachini (Gray, 1869) Scheffer, 1958
                                           Subtribe Monachina (Gray, 1869) R.H. Tedford, in M.C. McKenna & S.K. Bell, 1997
                                             01 Genus †Palmidophoca Ginsburg & Janvier, 1975
                                             02 Genus †Monachopsis Kretzoi, 1941
                                             03 Genus †Monotherium Van Beneden, 1876
                                             04 Genus †Pristiphoca (Gervais, 1852) Gervais, 1859
                                             05 Genus †Properiptychus Ameghino, 1897, nom. nud.
                                             06 Genus †Messiphoca de Muizon, 1981
                                             07 Genus †Mesotaria Van Beneden, 1876
                                             08 Genus †Callophoca Van Beneden, 1876
                                             09 Genus †Pliophoca Tavani, 1942
                                             10 Genus Mirounga Gray, 1827 - elephant-seals
                                             11 Genus Monachus Fleming, 1822 - monk seals