Vertebrata Cuvier, 1812 - vertebrates
   Gnathostomata
     Teleostomi
       Tetrapoda Hatschek & Cori 1896 [Gauthier, Kluge & Rowe 1988]
         Amniota Haeckel, 1866 [Gauthier, Kluge & Rowe 1988] - amniotes
           Class Mammalia Linnaeus, 1758 - mammals
             Subclass Theria Parker & Haswell, 1897
               Theria of Metatherian-Eutherian grade
                 Infraclass Eutheria Gill, 1872
                   Order Proboscidea Owen, 1859 - elephants
                     Suborder Euelephantoidea see Suborder Elephantiformes (Tassy, 1988)
                       1 Family †Gomphotheriidae Hay, 1922 - gomphotheres
                       2 Family Elephantidae Gray, 1821 - elephants