Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Ornithurae Haeckel, 1866 see Clade Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}
     Infraclass Ratitae (Merrem, 1813) P. Brodkorb, 1963 see Parvclass Ratitae (Merrem, 1813)
       Order Struthioniformes Latham, 1790
         Family †Eleutherornithidae Wetmore
           1 Genus †Eleutherornis Schaub, 1940