Chaetodon auriga

The threadfin butterflyfish (Chaetodon auriga) is a species of butterflyfish (family Chaetodontidae). Chaetodon auriga is found in the Indo-Pacific region, from the Red Sea and eastern Africa (south to Mossel Bay, South Africa) to the Hawaiian, Marquesas and Ducie islands, north to southern Japan, south to Lord Howe Island and Rapa Iti, at depths of 1–35 metres (3–115 ft). Chaetodon auriga is up to 23 centimetres (9 in) long. Its body is white with `chevron' markings on the side. Tear edge of the dorsal fin has a prominent black spot, and a prominent black vertical band runs through the eye. The rear of soft-dorsal fin has a trailing filament, and it has a belly patch of descending oblique dark lines as well as bright yellow fins. Two subspecies are sometimes recognised: Chaetodon auriga auriga occurs in the Red Sea population and lacks the dorsal eyespot; Chaetodon auriga setifer is the spotted population occurring outside the Red Sea. It belongs to the large subgenus Rabdophorus which might warrant recognition as a distinct genus. Within this group, it is almost certainly a rather close relative of the vagabond butterflyfish (C. vagabundus) and the Indian vagabond butterflyfish (C. decussatus). The C. auriga species group shares the characteristic pattern of two areas of ascending and descending oblique lines; species differ conspicuously in hindpart coloration.