A suborder of marine gastropod mollusks, where the gills tend to be involving the foot plus the mantle.
into the old systems of De Blainville and Cuvier, an order of nudibranchiate gastropods having lamellar gills under an expanded mantle, because the families Phyllidiidæ and Diphyllidiidæ.
In later on systems, a suborder of nudibranchiates extended to add types without branchiæ, but usually resembling the typical kinds. Thus extended, the order embraces the people Phyllidiidæ, Hypobranchæidæ, Pleurophylliidæ, and Dermatobranchiidæ.
Also Referred To As Inferobranchia, Hypobranchia, Hypobranchiata, Dipleurobranchia.