Bryozoans in this family form erect or encrusting colonies. Frontal wall well developed umbonuloid. Primary orifice without a sinus, uncalcified; obscured by calcified peristome and secondary orifice. Marginal areola present. Frontal spiramina evanescent or permanent, single or multiple. Avicularia usually present.

(Hayward and Ryland, 1999)