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 Anaspidea Fischer, 1883 - sea hares
         Superfamily Aplysioidea Lamarck, 1809
           Family Aplysiidae Lamarck, 1809
             Subfamily Aplysiinae Lamarck, 1809
               Genus Aplysia Linnaeus, 1767 - seahare
                 Subgenus Phycophila Adams, 1861