Bryozoans in this family may form unilaminar encrusting colonies, or erect colonies which may be unilaminar or multilaminar. Zooids have a well developed section of calcification on the frontal surface (the gymnocyst), which comprises one-third to one-half of the total zooid length and may be porous. Species lack avicularia, vibracular and broad-chambers,Bryozoans in this family may form unilaminar encrusting colonies, or erect colonies which may be unilaminar or multilaminar. Zooids have a well developed section of calcification on the frontal surface (the gymnocyst), which comprises one-third to one-half of the total zooid length and may be porous. The cryptocyst is present, but typically reduced and spines are a feature of some species. Species lack avicularia, vibracular and broad-chambers.