Saddleback Butterflyfish

Chaetodon falcula has a white body which is marked with a number of thin vertical dark grey lines. It has two clear black saddle-like blotches on the dorsal part of the body, a vertical black eye band and a black caudal peduncle. The dorsal, anal and caudal fins are yellow. The yellow continues onto the body adjacent to the dorsal and anal fins. There are 12–13 spines in the dorsal fin and 23–25 soft rays while the anal fin contains 3 spines and 20–21 soft rays. This species attains a total length of 20 centimetres (7.9 in).

Chaetodon falcula is found in the Indian Ocean where it occurs along the East African coast between Kenya and South Africa, Madagascar and the other western and central islands of the Indian Ocean, Sri Lanka, southern India, including the Andaman and Nicobar Islands, and from the waters of western Thailand east as far as Java. It occurs in the Cocos (Keeling) Islands, which are part of Australia, too.