Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795
       Order Caenogastropoda Cox, 1960 see Superorder Caenogastropoda Cox, 1960
         Superfamily Rissooidea Gray, 1847
           Family Rissoidae Gray, 1847
             Subfamily Rissoinae Gray, 1847
               Genus Pusillina Monterosato, 1884
                 Subgenus Ameririssoa Ponder, 1985