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 Helixarionoidea Bourguignat, 1883, orth. inval.
             1 Family Euconulidae Baker, 1928
             2 Family Helixarionidae Bourguignat, 1883, orth. inval. see Family Helicarionidae Bourguignat, 1877
             3 Family Ariophantidae Godwin-Austen, 1888
             4 Family Trochomorphidae Möllendorff, 1890
             5 Family Urocyclidae Simroth, 1889
             6 Family Cystopeltidae Cockerell, 1891 [monotypic]