Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Bivalvia Linnaeus, 1758 - bivalves
     Subclass Protobranchia Pelseneer, 1889
       Order Nuculida Dall, 1889
         Superfamily Nuculoidea Gray, 1824
           Family Nuculidae Gray, 1824 - nut clams
             Genus Nucula Lamarck, 1799
               1 Subgenus Nucula Lamarck, 1799
               2 Subgenus Lamellinucula Schenck, 1944