Colonies are massive, flat or hemispherical. Corallites are typically inclined on the colony surface, facing downwards on hemispherical surfaces. Corallite walls have sharp rims except for colonies from very shallow water. The lower part of the wall of inclined corallites is commonly immersed, giving the upper part a hooded appearance. Septa are widely spaced and irregular in size. Paliform crowns are well developed.