Sohal Tang

The Sohal Tang (Acanthurus sohal) is a striking, boldly striped surgeonfish endemic to the Red Sea, Gulf of Aden, and nearby Arabian Sea waters. It is one of the more aggressively territorial reef herbivores in its range, fiercely guarding shallow, surge-exposed grazing patches against rival tangs and other reef fish. Its body is patterned with alternating pale and dark bluish stripes running along the flanks, with bright orange trim along the dorsal and anal fins. The species is closely tied to shallow, wave-washed reef flats where strong currents support dense algal turf growth, and it plays an important role in controlling algae on Red Sea reefs.

• Stripes: Alternating bands of pale blue-gray and dark blue-black running the length of the body.
• Fin trim: Dorsal and anal fins edged in bright orange.
• Tail spine: Prominent white to pale scalpel-like spine at the base of the tail.
• Range cue: Endemic to the Red Sea and adjacent Arabian waters, unlike most other Acanthurus species with broader Indo-Pacific ranges.
• Look-alikes: Similar in general body shape to the Clown Tang (Acanthurus lineatus) of the wider Indo-Pacific, but the Sohal Tang's range and slightly different stripe coloration distinguish it.

Sohal Tangs are restricted to the Red Sea, Gulf of Aden, and nearby parts of the northwestern Indian Ocean, making them a regional endemic rather than a broadly distributed Indo-Pacific species. They inhabit shallow, high-energy reef flats and reef crest zones, typically in less than 5 meters of water, where constant wave surge supports dense algal turf. This shallow, wave-exposed habitat preference closely parallels that of the Clown Tang elsewhere in the Indo-Pacific. The species is rarely found on deeper reef slopes, remaining tied to the energetic shallow fringe of Red Sea reefs throughout its life.

Sohal Tangs are highly territorial, aggressively defending grazing patches on shallow reef flats against other herbivorous fish, including other surgeonfish and even much larger species that intrude on their turf. They spend most of the day grazing filamentous algae from exposed rock in the wave-swept shallows, using strong jaws adapted to feeding even amid heavy surge. This combative defense of grazing territory is thought to help maintain productive algal turf for the resident fish. Like other surgeonfish, the Sohal Tang uses its sharp caudal spine for defense when threatened. Reproduction follows a pelagic spawning pattern, with adults releasing eggs and sperm into open water, producing planktonic larvae that eventually settle onto shallow reef habitat.