Chevron Tang

The Chevron Tang is a striking surgeonfish (family Acanthuridae) named for the fine orange V-shaped, or chevron, markings that cover its body as a juvenile and subadult. Found on reefs of Hawaii and across the Indo-Pacific, it is prized in the aquarium trade for its dramatic coloration, though the pattern fades substantially as the fish matures, with adults becoming a more uniform dark brown. Like other members of its genus, it uses fine comb-like teeth to feed on algae and detritus from rock and coral surfaces. Populations are stable in the wild, though collection pressure for the aquarium trade has drawn some conservation attention in parts of its range.

• Body: Deep, oval, and moderately compressed, typical tang shape
• Color (juvenile/subadult): Dark brown to black body densely covered in narrow orange chevron (V-shaped) stripes
• Color (adult): Pattern fades to a more uniform dark brown or blackish tone with age
• Eyes and fins: Orange ring around the eye; fins often tinted orange
• Tail spine: Small, sharp scalpel-like spine at the tail base, characteristic of surgeonfish The density of fine chevron markings, much finer and more numerous than in related Ctenochaetus species, is the clearest identifier in younger individuals.

Chevron Tangs are found primarily around the Hawaiian Islands, with related populations extending across parts of the Indo-Pacific. They inhabit coral and rocky reef environments, typically at depths of 3-30 meters, in water temperatures around 22-27°C. They favor reef slopes and areas with a mix of rock, rubble, and coral where fine algal turf and detritus accumulate on surfaces, providing their primary food source. Juveniles are often found in more sheltered reef nooks, while adults range more openly across reef structure in search of grazing surfaces.

Chevron Tangs use specialized fine, comb-like teeth to sift algae, detritus, and diatoms from rock and coral surfaces, a feeding style that distinguishes Ctenochaetus species from the more direct algae-cropping of many other surgeonfish. They are typically solitary or found in loose small groups, showing territorial behavior toward conspecifics competing for the same grazing area, particularly as adults. Activity peaks during daylight hours, with individuals retreating to reef crevices at night. Like other surgeonfish, they are believed to spawn in open water, releasing eggs and sperm that develop into pelagic larvae, which drift with currents before settling onto reef habitat as juveniles displaying the species' signature chevron pattern.