General description:
Bryozoans in this family form encrusting colonies. The frontal surface is almost entirely underlain by an extensive cryptocyst; gymnocyst absent. Opesia reduced to a semicircular or subtriangular area coextensive with the operculum. Depressor muscles of the frontal membrane emerging through a pair of slit-like lateral opesiules situated a little below the opesia in the distal half of the autozooid. Operculum lightly chtinized, with a distinct marginal sclerite. Ovicells small, subimmersed closed by autozooidal operculum. Avicularia and spines absent. Vicarious vibracula occur at the distal end of the zooids, lacking a calcified pivotal bar. Vertical walls with large multiporous septula
(Hayward and Ryland, 1998)
Taxonomic name: