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
         (Helicid Sigmurethra)
           Superfamily Polygyroidea Pilsbry, 1895 see Superfamily Helicoidea Rafinesque, 1815
             1 Family Polygyridae Pilsbry, 1895
             2 Family Thysanophoridae Pilsbry, 1926