Kingdom Animalia Linnaeus, 1758 - animals
   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 Cephalaspidea Fischer, 1883
           Genus Acteon Montfort, 1810
           Genus Aglaja Renier, 1807
           Genus Bulla Linnaeus, 1758
           Genus Haminoea Turton, 1830
           Genus Retusa Brown, 1827
           Genus Scaphander Montfort, 1810