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 Akeridae Mazzarelli, 1891 [monotypic] Genus Akera Müller, 1776