Mollusca Linnaeus, 1758 - molluscs see Phylum Mollusca Linnaeus, 1758
   Gastropoda Cuvier, 1795 see Class Gastropoda Cuvier, 1795
     Clade Heterobranchia Burmeister, 1837 see Superorder Heterobranchia Burmeister, 1837
       Informal Group "Lower Heterobranchia"
         01 Family Cimidae Warén, 1993
         02 Family †Dolomitellidae Bandel, 1994
         03 Family †Heterosubulitidae Bandel, 2002
         04 Family †Kuskokwimiidae Frýda & Blodgett, 2001
         05 Family †Misurinellidae Bandel, 1994
         06 Family Orbitestellidae Iredale, 1917
         07 Family Tjaernoeiidae Warén, 1991
         08 Family Xylodisculidae Warén, 1992
         09 Superfamily Acteonoidea d'Orbigny, 1843
         10 Superfamily Architectonicoidea Gray, 1850
         11 Superfamily Glacidorboidea Ponder, 1986
         12 Superfamily Mathildoidea Dall, 1889
         13 Superfamily †Nerineoidea Zittel, 1873
         14 Superfamily Omalogyroidea Sars, 1878
         15 Superfamily Pyramidelloidea Gray, 1840
         16 Superfamily Ringiculoidea Philippi, 1853
         17 Superfamily Rissoelloidea Gray, 1850
         18 Superfamily †Streptacidoidea Knight, 1931
         19 Superfamily Valvatoidea Gray, 1840