Class Mammalia Linnaeus, 1758 - mammals
   Subclass Boreosphenida Luo, Cifelli & Kielan-Jaworowska, 2001 - tribotherians see Clade Boreosphenida Luo, Cifelli & Kielan-Jaworowska 2001
     Infraclass Eutheria Gill, 1872
       Magnorder Epitheria McKenna, 1975 see Cohort Placentalia Owen, 1837
         Superorder Ungulatomorpha Archibald, 1996
           Order †"Condylarthra" Cope, 1881 [paraphyletic]
             Family †"Arctocyonidae" Giebel, 1855 [monophyletic?]
               Genus †Protungulatum Sloan & Van Valen, 1965
                 1 †Protungulatum donnae Sloan & Van Valen, 1965