Phylum Mollusca Linnaeus, 1758 - molluscs Class Bivalvia Linnaeus, 1758 - bivalves Subclass Heterodonta Neumayr, 1884 see Clade Heterodonta Neumayr, 1884 Order Venerida Gray, 1854 Superfamily Lucinoidea Fleming, 1828 Family Thyasiridae Dall, 1900 (1895) Genus Axinus Sowerby, 1821