Superphylum Deuterostomia Grobben, 1908 - deuterostomes see Infrakingdom Deuterostomia Grobben, 1908
   Phylum Chordata Bateson, 1885 - chordates
     Subphylum Craniata auct. see Subphylum Vertebrata Cuvier, 1812
       Vertebrata (Lamarck, 1801) - vertebrates see Subphylum Vertebrata Cuvier, 1812
         Myopterygii - myopterygians
           Superclass Gnathostomata Gegenbaur, 1874 - jawed vertebrates
             Grade Chondrichthiomorphi
               Class Chondrichthyes Huxley, 1880 - cartilaginous fishes
                 Subclass Holocephali Bonaparte, 1832
                   Superorder †Paraselachimorpha (Lund, 1977)
                     1.1 [plesion] Family †Gregoriidae Lund & Grogan, 2004
                     1.2.1 Order †Orodontiformes Zangerl, 1981 [monotypic]
                     1.2.2 ?Order †Petalodontiformes Zangerl, 1981
                     1.2.3 Order †Helodontiformes Patterson, 1965 [monotypic]
                     2.1 Order †Iniopterygiformes Zangerl & Case, 1973
                     2.2 Order †Debeeriiformes [monotypic]
                     3 ?Order †Eugeneodontiformes Zangerl, 1981