Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
             Class Mammalia Linnaeus, 1758 - mammals
               Subclass Eutheria Gill, 1872 see Infraclass Eutheria Gill, 1872
                 Superorder Mesaxonia (Marsh, 1884)
                   Order Perissodactyla Owen, 1848 - odd-toed ungulates
                     1 Suborder †Ancylopoda Cope, 1889 see Superfamily Chalicotherioidea Gill, 1872
                     2 Suborder Hippomorpha Wood, 1937
                     3 Suborder Ceratomorpha Wood, 1937