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 Mactrinae Lamarck, 1809
               Genus Mactra Linnaeus, 1767
                 01 Subgenus Austromactra Iredale, 1930
                 02 Subgenus Coelomactra Dall, 1895
                 03 Subgenus Cyclomactra Dall, 1895
                 04 Subgenus Diophoromactra Vaught, 1989, orth. inval. see Subgenus Diaphoromactra Iredale, 1930
                 05 Subgenus Electomactra Iredale, 1930
                 06 Subgenus Longimactra Finlay, 1928
                 07 Subgenus Maorimactra Finlay, 1928
                 08 Subgenus Mactrinula Gray, 1853
                 09 Subgenus Mactroderma Dall, 1894
                 10 Subgenus Mactrotoma Dall, 1894
                 11 Subgenus Micromactra Dall, 1894
                 12 Subgenus Simomactra Dall, 1894
                 13 Subgenus Nannomactra Iredale, 1930