living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Mollusca Linnaeus, 1758 - molluscs
           Class Gastropoda Cuvier, 1795 - snails and slugs
             Subclass Opisthobranchia Milne-Edwards, 1848 - opisthobranchs see Order Opisthobranchia Milne-Edwards, 1848
               Order Nudibranchia Cuvier, 1814 - "true" nudibranchs
                 Suborder Aeolidoidea see Suborder Aeolidina Odhner, 1934
                   Superfamily Acleioprocta Odhner, 1939 see Superfamily Fionoidea Gray, 1857
                     1 Family Eubranchidae Odhner, 1934
                     2 Family Pseudovermidae Thiele, 1931
                     3 Family Tergipedidae Bergh, 1889
                     4 Family Fionidae Alder & Hancock, 1855
                     5 Family Calmidae Iredale & O'Donoghue, 1923