Phylum [Vertebrata] Lamarck, 1801 see Infraphylum Vertebrata Lamarck, 1801
   Class Chondrichthyes Huxley, 1880 - cartilaginous fishes
     Subclass Elasmobranchii Bonaparte, 1838 - shark-like fishes see Infraclass Elasmobranchii Bonaparte, 1838
       Order †Symmoriida Zangerl, 1981 see Order Symmoriiformes Zangerl, 1981
         1 Genus †Cobelodus Zangerl, 1973
         2 Genus †Stethacanthus Newberry, 1890
         2.0 Genus †"Stethacantus" see Genus Stethacanthus Newberry, 1890