The butterflyfish belongs to the butterflyfish family of the order Perciformes. Butterflyfish is a collective name for more than 150 species of small, fast-swimming saltwater fish found in tropical coral reefs. This type of fish has a large body, flat, thin sides, a dorsal fin, and a small mouth with brush-like teeth. The palates sometimes extend into a fairly long snout. They are all small and rarely exceed 20 cm in length. Because its swimming posture resembles that of a butterfly and its colors are extremely bright, it is also called a butterflyfish.
Butterflyfish
The genus Butterflyfish (scientific name: Chaetodon) is a family of marine fish that lives in tropical to warm temperate waters. Some of them appear in brackish estuaries or enclosed bays and generally move along slopess steep rocky reefs. They are most common near coral reefs in shallow water (less than 20 meters), and some live in deep water below 200 meters. They are found around seagrass habitats, deep mudflats or shallow lagoons. Many butterflyfish larvae live in different areas than adult fish, such as tidal lagoons, rocky coral reefs, and shallow waters without corals.
The body is diamond-shaped or almost oval and is very flattened laterally. The mouth is small, positioned at the end and slightly retractable; the teeth of the jaw are thin, forming long and narrow brush-shaped dental belts on the upper and lower jaws. The preoperculum is smooth, but in juveniles it may be serrated or spiny. The body is covered with weak, medium or small comb scales, or scalesrounds. The lateral line is complete and curved, but not obvious. Young fish are called Tholichthys because they have bony plates on their heads. The dorsal fin is continuous, with shallow notches between the hard spines and soft rays; the pelvic fin is on the chest, with axillary scales; the caudal fin is generally truncated or rounded.
Most butterfly fish live in shallow water less than 20 meters. They are very typical diurnal fish. They come out to find food and mate during the day, and hide in reef caves to rest at night. When feeding, they may travel in groups, in pairs, or alone. Eating habits vary considerably. Some eat small invertebrates and algae hidden in cracks in the reef surface, some catch zooplankton in the water layer, and some only eatue living coral polyps. It moves quickly and hides in coral reefs or rock crevices when disturbed. They must go through a long period of drift during their lives, making artificial reproduction difficult to succeed.
(Baidu Encyclopedia)