The largest of all parrotfish, the humphead parrotfish (Bolbometopon muricatum) is an olive or blue-green to slate-grey fish, with a yellowish to pink head. Its most distinctive feature, and the reason for its common name, is the prominent bulbous forehead which develops in adults. Juvenile humphead parrotfish do not have this bulging head and also differ slightly in colour, being green or brown with five vertical rows of small, whitish spots. Parrotfish get their name from their peculiar teeth, which are fused into a parrot-like beak. They also have teeth at the back of the throat which grind food