Class Bivalvia Linnaeus, 1758 - bivalves
   Subclass Autobranchia Grobben, 1894
     Superorder Heteroconchia Gray, 1854
       Clade Heterodonta Neumayr, 1884
         Order Pholadomyida Newell, 1965
           Septibranchia Pelseneer, 1888
             Superfamily Cuspidarioidea Dall, 1886
               ?Family Spheniopsidae Gardner, 1928