Phylum [Vertebrata] (Lamarck, 1801) Class Chondrichthyes Huxley, 1880 - cartilaginous fishes Subclass Elasmobranchii Bonaparte, 1838 - shark-like fishes Order †Xenacanthida Glikman, 1964 see Order Xenacanthiformes Berg, 1955 Genus †Xenacanthus Beyrich, 1848