Phylum Mollusca Linnaeus, 1758 - molluscs Class Bivalvia Linnaeus, 1758 - bivalves Subclass Heterodonta Neumayr, 1884 see Clade Heterodonta Neumayr, 1884 Order Chamida see Order Venerida Gray, 1854 Superfamily Cardioidea Lamarck, 1809 Family Cardiidae Lamarck, 1809 - cockles Subfamily Trachycardiinae Stewart, 1930 Genus Papyridea Swainson, 1840