Crown-of-thorns starfish (Acanthaster planci) eating coral, time-lapse footage. This is a poisonous starfish that lives on coral reefs in the Indo-Pacific region. It has 12 to 19 arms and long spines on its upper surface. The epithelial cells covering the spines contain glands that release poison into the skin of an attacker. Its mouth is on its lower side, feeding on the polyps that build a coral reef. It can reach 45 centimetres across. The increase in numbers of this starfish, resulting from human decimation of its chief predator, poses a serious threat to coral reefs. Filmed at Bunaken Island, Sulawesi, Indonesia. Bunaken Island still has almost pristine coral reefs, supporting a rich diversity of marine life.