Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Bivalvia Linnaeus, 1758 - bivalves
     Subclass Anomalodesmata Dall, 1889 [monotypic] see Order Anomalodesmata Dall, 1889
       Order Pholadomyida Newell, 1965
         Suborder Pholadomyina Newell, 1965 see Order Pholadomyida Newell, 1965
           Superfamily Pandoroidea Rafinesque, 1815
             Family Lyonsiidae Fischer, 1887
               Genus Lyonsia Turton, 1822
                 1 Subgenus Lyonsia Turton, 1822
                 2 Subgenus Bentholyonsia Habe, 1952
                 3 Subgenus Endomargarus Cossmann, 1886