Characters: Colonies are composed of contorted branches, sometimes with flat laminar bases. Stands over 5 metres across and one metre high are not unusual. Corallites are 4-6 millimetres diameter, thick walled and have six thick primary septa. The coenosteum is covered with tall spinules. Colour: Dark brown, cream or green. Similar species: Echinopora gemmacea, which does not form extensive branches. Echinopora mammiformis has a smooth coenosteum with distinctively coloured corallites. Habitat: Forms large stands on protected horizontal substrates including shallow reefs and lagoons. Abundance: Uncommon.