Chordata Bateson, 1885 - chordates Class Elasmobranchii Bonaparte, 1838 see Subclass Elasmobranchii Bonaparte, 1838 Subclass Selachii see Subdivision Selachii Order †Acanthodei Gunnell, 1933 see Class Acanthodii Owen, 1846 Family †Acanthoëssidae see Family Acanthodidae Huxley, 1861