Characters: Colonies are up to 2 metres across and are primarily encrusting. Large colonies have upright or inclined bifurcating branches up to 0.2 metres long. They mostly have flattened ends. Verrucae are irregular. On inclined branches these are better developed on upper surfaces. Branches are tall and upright, almost cylindrical in section, becoming flattened towards the tip. Verrucae are elongate but have irregular sizes and are irregularly distributed on branches. Corallites are closely compacted and cellular, with one septum more developed than the others. Colour: Greenish-brown. Similar species: Pocillopora effusus, which has less development of branches and has larger, less crowded corallites. See also P. woodjonesi, which has substantially larger, less compact, branches. Habitat: Shallow reef environments exposed to strong wave action. Abundance: Uncommon.