Mammaliaformes Rowe 1988, nom. cl. inval. see Clade Mammaliaformes Rowe 1988 [Rowe 2020]
   [crown] Mammalia Linnaeus 1758 [Rowe 1988], nom. cl. inval. see Clade Mammalia Linnaeus 1758 [Rowe 2020]
     Theriimorpha Rowe 1993
       Theria Parker & Haswell 1897 [McKenna 1975] see Subclass Theria Parker & Haswell, 1897
         Metatheria Huxley 1880 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Infraclass Metatheria Huxley, 1880
           Marsupialia Jameson 1818 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Cohort Marsupialia Jameson, 1818
             Didelphimorphia Gill 1872 see Order Didelphimorphia Gill, 1872
               Genus Didelphis Linnaeus, 1758 - large American opossums
                 Didelphis virginiana Kerr, 1792 - Virginia opossum