Striped Surgeonfish

This species reaches about 38 centimeters in length. Much of the body has black-edged blue and yellow stripes, and the top of the head is striped with yellow. The belly is grayish. The pectoral fins have darkened rays and the pelvic fins are yellow-brown with black margins. Individuals from around the Philippines vary in coloration. A. lineatus, like other surgeonfish, possesses a sharp spine on either side of the tail base, but unlike in other surgeonfish, the spines are venomous and capable of inflicting painful wounds on handlers.

A. lineatus occurs in the Indian Ocean from East Africa to the western Pacific Ocean to the Great Barrier Reef, Japan, Polynesia, and Hawaii.

The fish is territorial, with a large male defending a feeding territory and a harem of females. The adults may also school, and they gather en masse during spawning. The juvenile is solitary. The fish is mostly herbivorous, but might eat crustaceans at times. Most of its diet is algae. It grazes during the day. Acanthurus lineatus species found in Australia, in the Indian Ocean have a greater defense rate against intruders. Lined surgeonfish in the Indian Ocean have a smaller body size, allowing them to have greater access and abundance of food, due to hurricane damage to reefs, enhancing the overall algal turfs that Acanthurus lineatus feed on.

This species is of commercial and ornamental value. It is especially important among the reef fishes of American Samoa. In some areas it is heavily exploited, but it lives in many protected zones and in general it is widespread and common.

Acanthurus lineatus has the specific name lineatus, meaning "lined", a reference to the yellow and black lines on the body of this fish.