Characters: Colonies are encrusting and usually small. Corallites are cerioid, with irregular angular shapes. A central corallite is usually conspicuous. Septa are compact and columellae are small. Colonies are not fleshy. Colour: Usually pale grey, brown or rust coloured, often mottled. Similar species: Superficially resembles small colonies of the faviid Moseleya latistellata. If a central corallite is inconspicuous it resembles the faviid Favites. See also Acanthastrea hemprichii. and A. rotundoflora. Habitat: Lower reef slopes protected from wave action. Abundance: Rare except in subtropical localities of eastern Australia.
Characters: Colonies are hemispherical. Corallites are immersed to conical or tubular, usually face different directions and are of mixed sizes, giving a chaotic appearance. The coenosteum is covered with papillae that are inclined on the surface. Colour: Pale cream, green or brown. Similar species: Astreopora myriophthalma, which has an orderly arrangement of corallites. Habitat: A wide range of environments, especially in shallow turbid water. Abundance: Sometimes common