subclass Opisthobranchia

Noun

1.

subclass Opisthobranchia - gastropods having the gills when present posterior to the heart and having no operculum: includes sea slugs; sea butterflies; sea hares Synonyms: Opisthobranchia

class, class Gasteropoda, class Gastropoda, Gasteropoda, Gastropoda, Nudibranchia, Opisthobranchia, order Nudibranchia