The signature fish of this sea and one of its best-known endemics: 40 cm (16 in) of blue-black body ruled with fine horizontal white and olive lines, a crescent tail edged in blue, and an orange patch running back from the pectoral fin toward a bright blue tail base.
That blue patch is a warning label. Inside it, on each side of the tail base, sits a hinged blade that folds into a groove and flicks out when the fish tenses - a scalpel of modified scale, sharp enough to cut skin and used sideways with a flick of the body. The whole family is named for it. A sohal will use it on other fish, on a hand, and on a camera dome.
It is a farmer with a temper. Each adult holds a patch of algae-covered reef top in the surge zone, grazes it, and drives off everything that tries to feed there - other surgeonfish, parrotfish, and divers who linger. Chasing a snorkeler out of a territory is routine behavior, not an anomaly, and it happens in the top two meters of water where these fish live.
Forsskal described it in 1775 from this coast on the Danish expedition that killed him, and the name comes straight from Arabic. It is a fish that exists nowhere else on Earth, and it is on the reef flat in front of nearly every hotel on this coast.
The genus. Acanthurus Forsskål 1775 - acanthus (thorn or spine) + oura (tail). ETYFish
The species. Acanthurus sohal (Forsskål 1775) - Arabic name for this fish. ETYFish
- blue-black body ruled with fine horizontal white and olive lines
- orange patch behind the pectoral fin
- bright blue base to the tail, marking the blade
- in the top two meters of the reef edge, often chasing other fish
Why it's threatened
Threat classification from the IUCN Red List.
