Black-nosed Butterflyfish, Johnrandallia nigrirostris

The Black-nosed Butterflyfish (Johnrandallia nigrirostris), also known as the Barberfish, the Barber, or Butterfly Barber, is a species of fish in the Chaetodontidae family of butterfly fishes. This fish is sometimes referred to as a cleaner fish. It is the only member of its genus and named after the ichthyologist John E. Randall.

It is found in the East Pacific Ocean from the Gulf of California to Panama, including Cocos Island, Malpelo Island, and the Galapagos Islands. It has also been found in Peru. It is found at depths ranging from the surface to 130 feet below sea level. Its habitat is coral reefs and rocky areas.

This fish has a silvery-yellow, compressed body and grows to about 8 inches in length. It is marked with black bands along the base of its dorsal fin, and on its snout and forehead. It has a small protractile mouth with a black, burglar-like mask around its eyes. It has brush-like teeth.

The Black-nosed Butterflyfish collects in small groups. It feeds during the day, at which time it remains highly active. It shelters near the reef surface at night. Like that of a true cleaner fish, this species will sometimes remain a cleaning station where infested fishes come to have various crustaceans and ectoparasites removed.

This species feeds on crustaceans, mollusks, and algae.

Image Caption: Johnrandallia nigrirostris Shot at Machete dive site in the Coiba National Park, Panama. Credit: LASZLO ILYES/Wikipedia(CC BY 2.0)