Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Heterobranchia Burmeister, 1837 [monotypic] see Superorder Heterobranchia Burmeister, 1837
       Order Heterostropha Fischer, 1885
         Superfamily Rissoelloidea Gray, 1850
           1 Family Rissoellidae Gray, 1850 [monotypic]
           2 Family Omalogyridae Sars, 1878
           3 Family Cimidae Warén, 1993
           4 Family Xylodisculidae Warén, 1992 [monotypic]
           5 Family Cornirostridae Ponder, 1990
           6 Family Hyalogyrinidae Warén & Bouchet, 1993 [monotypic]