The Blue Surgeonfish (Acanthurus leucosternon ) can reach an average size of 23 cm (9 in) in length. The body has an oval shape and is
compressed laterally. Like other surgeonfishes , the Blue surgeonfish swims with its pectoral
fins. The caudal fin has a crescent shape. The fish has a "surgeon's scalpel," an erected part of the
spine located at the base of the tail.The mouth is small and pointed in a beak-like manner with tiny
and sharp teeth for reaching narrow spaces of food. Its sides are blue; its dorsal fin and the base
of caudal fin are yellow; the head is black; the mouth, the throat area, the anal and pelvic fins are
white. The pectoral fins are transparent with yellow reflections.