Opisthobranchia

== Translingual == === Etymology === From opisthobranch (“with the gills behind the heart”). === Proper noun === Opisthobranchia (obsolete) A taxonomic subclass within the class Gastropoda – a polyphyletic taxon including all opisthobranchs; some core members are now classified as the Euopisthobranchia. ==== Derived terms ==== Euopisthobranchia === References === Opisthobranchia at World Register of Marine Species