Class Bivalvia Linnaeus, 1758 - bivalves Subclass Autobranchia Grobben, 1894 Superorder Pteriomorphia Beurlen, 1944 Order Pteriida Newell, 1965 Superfamily Pterioidea Gray, 1847 (1820) Family Isognomonidae Woodring, 1925 (1828)