[Phylum] Chordata Bateson, 1885 - chordates Subphylum Craniata auct. Infraphylum Vertebrata Lamarck, 1801 - vertebrates Superclass Gnathostomata Gegenbaur, 1874 - jawed vertebrates Class †Acanthodii Owen, 1846 - acanthodians Family †Machaeracanthidae Burrow & Young, 2005, incertae sedis 1 Genus †Machaeracanthus Newberry, 1857