Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Divasibranchia Minichev & Starobogatov, 1975
       Order Stylommatophora Schmidt, 1855 see Infraorder Stylommatophora Schmidt, 1855
         (Achatinid Sigmurethra)
           Suborder Sigmurethra Pilsbry, 1900 see Group Sigmurethra Pilsbry, 1900
             Superfamily Acavoidea Pilsbry, 1895
               Family Megomphicidae Baker, 1930
                 1 Genus Megomphix Baker, 1930
                 2 Genus Ammonitella Cooper, 1869
                 3 Genus Polygyrella Bland, 1869
                 4 Genus Polygyroidea Pilsbry, 1924