Phylum Chordata Bateson, 1885 - chordates Subphylum Vertebrata Cuvier, 1812 - vertebrates see Infraphylum Vertebrata Lamarck, 1801 Pisces Class Chondrichthyes Huxley, 1880 - cartilaginous fishes Subclass Elasmobranchii Bonaparte, 1838 - shark-like fishes see Infraclass Elasmobranchii Bonaparte, 1838 Order Hexanchiformes Compagno, 1973 - six-gill sharks Family Chlamydoselachidae Garman, 1884 - frill sharks Family Hexanchidae Gray, 1851 - cow sharks