Characters: Small colonies have encrusting, laminar or submassive bases with short columns or branches. Large colonies are hemispherical, consisting of compact fused branches. Branches are sometimes flattened towards their tips. Monticules are low and rounded. Tentacles are extended day and night; they are long and shaggy and of uniform length. Colour: Polyps are dark brown or blue-grey, tentacles have white tips. Similar species: Hydnophora exesa, which may have better development of branches and more exsert monticules. Underwater the extended polyps are Scapophyllia-like. Habitat: Shallow reef environments protected from strong wave action. Abundance: Uncommon.