Characters: Colonies are flat plates in tiers or whorls, sometimes with columns, sometimes encrusting or forming irregularly contorted laminae. Corallites are immersed. There are no tuberculae or papillae. The coenosteum is coarse. Colour: Uniform purple, blue or brown. Similar species: Montipora turgescens, which has smaller corallites and a finer coenosteum. See also M. florida and M. friabilis, which have much more delicate, and thinner fronds and smaller corallites. Habitat: Mostly lagoons. Abundance: Sometimes common.