ctenidiobranchiata

from The Century Dictionary.

• A suborder or superfamily of zygobranchiate gastropods, having paired ctenidia functioning as gills. It contains the Haliotidæ and Fissurellidæ, or seaears and keyhole-limpets.
• A suborder of palliate or tectibranchiate opisthobranchiate gastropods, containing those which retain the ctenidia as functional gills, as the Tornatellidæ, Bullidæ, Aplysiidæ, etc.