Class Bivalvia Linnaeus, 1758 - bivalves Subclass Autobranchia Grobben, 1894 Superorder Heteroconchia Gray, 1854 Clade Heterodonta Neumayr, 1884 Order Myida Stoliczka, 1870 Superfamily Pholadoidea Lamarck, 1809 Family Pholadidae Lamarck, 1809 - piddocks Subfamily Pholadinae Lamarck, 1809