Characters: Colonies are usually hemispherical or helmet-shaped and may be over 4 metres across. They commonly form ‘micro-atolls’ in intertidal habitats. The surface is usually smooth. Colour: Usually cream or pale brown but may be bright blue, purple or green in shallow water. Similar species: Porites solida. See also P. australiensis, which is distinguished by having taller pali, especially on the lateral pairs of septa. Habitat: Frequently a dominant species of back reef margins, lagoons and some fringing reefs. Abundance: Probably the most common Porites.