Vertebrata Cuvier, 1812 - vertebrates Gnathostomata Class Chondrichthyes Huxley, 1880 - cartilaginous fishes Subclass Holocephali Bonaparte, 1832 Order Chimaeriformes Obruchev, 1953 - chimaeras Suborder Chimaeroidei Patterson, 1965 Family Callorhinchidae Garman, 1901 - plownose chimaeras