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 Gymnosomata Blainville, 1824 - naked pteropods see Suborder Gymnosomata Blainville, 1824 Family Pneumodermatidae Latreille, 1825 Genus Platybrachium Minichev, 1976