Phylum Mollusca Linnaeus, 1758 - molluscs
   Subphylum Conchifera Gegenbauer, 1878
     Class Gastropoda Cuvier, 1795 - snails and slugs
       Subclass Orthogastropoda Ponder & Lindberg, 1995
         Superorder Heterobranchia Burmeister, 1837
           Order Opisthobranchia Milne-Edwards, 1848
             Suborder Notaspidea Fischer, 1883
               Superfamily Tylodinoidea J.E. Gray, 1847 see Superfamily Umbraculoidea Dall, 1889 (1827)
                 1 Family Tylodinidae Gray, 1847
                 2 Family Umbraculidae Dall, 1889 (1827)