Class Bivalvia Linnaeus, 1758 - bivalves Subclass Autobranchia Grobben, 1894 Superorder Heteroconchia Gray, 1854 Clade Heterodonta Neumayr, 1884 Order Venerida Gray, 1854 Superfamily Gaimardioidea Hedley, 1916 [monotypic] 1 Family Gaimardiidae Hedley, 1916