living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
             Class Mammalia Linnaeus, 1758 - mammals
               Subclass Theria Parker & Haswell, 1897
                 Infraclass Eutheria Gill, 1872
                   Order Artiodactyla Owen, 1848 - even-toed ungulates see Order Cetartiodactyla Montgelard, Catzeflis & Douzery, 1997
                     Suborder Suiformes Jaeckel, 1911 see Suborder Suina Gray, 1868
                       Family Hippopotamyidae see Family Hippopotamidae Gray, 1821
                         Genus Choeropsis Leidy, 1853 - pygmy hippopotamus
                           Choeropsis liberiensis (Morton, 1844) - pygmy hippopotamus