Chevron Butterflyfish

The Chevron Butterflyfish (Chaetodon trifascialis), also referred to as the Chevroned Butterflyfish, Triangulate Butterflyfish, or V-Lined Butterflyfish, is a marine ray-finned fish species belonging to the family Chaetodontidae. This species is widely distributed across the Indo-Pacific region. It should not be mistaken for the Melon Butterflyfish (Chaetodon trifasciatus), Three-Striped Butterflyfish (Chaetodon tricinctus), or Three-Banded Butterflyfish (Chaetodon robustus).

The Chevron Butterflyfish is characterized by its relatively elongate, pale body adorned with distinctive dark vertical chevron markings. It features a black tail with a yellow posterior margin and a black band with pale edges running through its eye. Juveniles display a black vertical band extending from the rear of the dorsal fin across the body to the rear of the anal fins, accompanied by a yellow tail base and pectoral fins. The species’ dorsal fin contains 13-15 spines and 14-16 soft rays, whereas the anal fin comprises 3-5 spines and 13-15 soft rays. The maximum total length attained by this species is 18 centimeters (7.1 inches).

The distribution of the Chevron Butterflyfish spans a wide area within the Indo-Pacific region. It is prevalent in the undefined, from the coastal regions of East Africa from 🇪🇬 Egypt to 🇿🇦 South Africa, across the 🌊 Indian Ocean, and extends into the 🌊 Pacific Ocean reaching the Line Islands, Johnston Atoll, and the Howland and Baker Islands in the central-west Pacific. The northern range extends to southern 🇯🇵 Japan, while the southern limit reaches Lord Howe Island and Rapa Iti. In 🇦🇺 Australia, this species is found from the Houtman Abrolhos to Beagle Reef, including the Rowley Shoals and Scott Reef in Western Australia, extending to the northern Great Barrier Reef off Queensland, certain reefs in the Coral Sea, and as far south as Arrawarra Headland near Coffs Harbour in New South Wales. It is also found around 🇦🇺 Australia’s 🌊 Indian Ocean territories, the Cocos (Keeling) Islands, and Christmas Islands.

This territorial species inhabits semi-protected seaward and shallow lagoon reefs, with a close association to tabular and staghorn (Acropora) corals, which provide its primary diet of polyps and mucus. Its habitat ranges from depths of 2 to 30 meters. Adult Chevron Butterflyfish are typically observed swimming alone or in pairs during the breeding season, while juveniles remain concealed among coral branches. The species is oviparous.