Parrotfish, a collective name for the fish of the order Parrotfish of the suborder Bulbophyllaceae, is named for its resemblance to the mouth shape of a parrot' mouth. The body color is very bright, the males are mostly bluish blue, and the females are dull. It is found in tropical and subtropical coral reef waters. They are a very distinctive type of coral reef fish, basically inhabit between coral reefs or rock reefs, feeding on corals, shellfish, sea urchins and other invertebrates and algae, according to scientists' research confirmed that parrotfish is the most important producer of fine coral sand in the coral reef area.
The body is oblong and flattened laterally. The head is short and tall, with a sharp crest on the dorsal margin. The mouth is large and anterior; the maxilla is fixed in the premaxilla, and the mouth cannot protrude forward; most of the two jaw teeth are healed into tooth plates, shaped like the mouth of a parrot. The upper lip splits into the inner and outer lips. The anterior gill cap is smooth , the body is covered with medium large round scales , and the cheeks are generally scaleless or only scaled behind the eyes. Parrotfish are close to the bulge, but their mouths cannot stick out, while the teeth of their upper and lower jaws can be joined, and their upper and lower pharyngeal skulls are strong enough to crush corals.
Like the rumped fish, parrotfish undergo a sexual transition after the female matures. Most parrotfish have juvenile and adult fish that differ greatly in color and markings. Juveniles and females are generally brown in color with 5-6 blue transverse bands on the side of the body. The male is bluish-blue and has a variety of other colours of spots or stripes, with pale brown leading edges of the scales and blue stripes on the dorsal, and caudal fins. Because the body color of parrotfish is mainly blue and green, and the difference in color is not obvious, it is difficult to identify their species from the appearance.