Phylum Mollusca Linnaeus, 1758 - molluscs Class Bivalvia Linnaeus, 1758 - bivalves Subclass Protobranchia Pelseneer, 1889 Order Nuculida Dall, 1889 1 Superfamily Nuculoidea Gray, 1824 2 Superfamily Nuculanoidea Adams & Adams, 1858 (1854) 3 Superfamily †Ctenodontoidea Wöhrmann, 1893, nom. illeg. [monotypic]