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 Opisthobranchia Milne-Edwards, 1846 see Order Opisthobranchia Milne-Edwards, 1848
         1 Clade Cephalaspidea Fischer, 1883 see Order Cephalaspidea Fischer, 1883
         2 Clade Thecosomata Gray, 1840 see Suborder Thecosomata Blainville, 1824
         3 Clade Gymnosomata Blainville, 1824 see Suborder Gymnosomata Blainville, 1824
         4 Clade Aplysiomorpha Pelseneer, 1906 see Suborder Aplysiomorpha Pelseneer, 1906
         5 "Group" Acochlidiacea Odhner, 1937 see Suborder Acochlidiacea Odhner, 1937
         6 Clade Sacoglossa Ihering, 1876 see Order Sacoglossa Ihering, 1876
         7 "Group" Cylindrobullida Baba, 1966 see Suborder Sacoglossa Ihering, 1876
         8 Clade Umbraculida Schmekel, 1985 see Order Umbraculida Schmekel, 1985
         9 Clade Nudipleura Wägele & Willan, 2000