Phylum Mollusca Linnaeus, 1758 - molluscs Class Bivalvia Linnaeus, 1758 - bivalves Subclass Heterodonta Neumayr, 1884 see Clade Heterodonta Neumayr, 1884 Order Venerida Gray, 1854 Superfamily Carditoidea Férussac, 1822 1 Family Carditidae Férussac, 1822 - little heart shells 2 Family Condylocardiidae Bernard, 1896