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 Mactroidea Lamarck, 1809
           Family Mactridae Lamarck, 1809 - surf clams
             Subfamily Lutrariinae Gray, 1853
               1 Genus Lutraria Lamarck, 1799
               2 Genus Eastonia Gray, 1853
               3 Genus Heterocardia Deshayes, 1855
               4 Genus Meropesta Iredale, 1929
               5 Genus Tresus Gray, 1853