CICHLIDS, SURFPERCHES, AND RELATIVES: Labroidei

PHYSICAL CHARACTERISTICS

Cichlids (SIH-cluhds), surfperches, damselfishes, wrasses, parrotfishes, and rock whitings have a second set of jaws in the throat. These fishes have a dorsal fin that extends the length of the fish's back. The dorsal (DOOR-suhl) fin is the one along the midline of the back.

GEOGRAPHIC RANGE

Cichlids live in South America, Africa, Asia, and North America. Surfperches live in coastal areas of the northern part of the Pacific Ocean. Parrotfishes, wrasses, and damselfishes live in the Atlantic, Pacific, and Indian oceans. Rock whitings live in Australia and New Zealand.

HABITAT

Cichlids live in freshwater in lakes, swamps, streams, and rivers, including rapids. Surfperches live in saltwater near sandy beaches, sea grass beds, rocky outcroppings, and piers. Damselfishes, wrasses, parrotfishes, and rock whitings live on reefs, although a few species live in the open sea.

DIET

Many cichlids hunt other fishes and eat them whole. Some scrape algae from rocks. Some eat animal plankton. One species eats plant plankton. Many cichlids have special teeth for crushing the shells of snails. Surfperches eat crustaceans, mollusks, and worms. Damselfishes, parrotfishes, and rock whitings eat plants and animals. Some wrasses eat hard-shelled invertebrates, or animals without a backbone. Others eat plankton. Cleaner wrasses eat parasites and waste they find on other fishes. Crustaceans (krus-TAY-shuns) are water-dwelling animals that have jointed legs and a hard shell but no backbone. Mollusks (MAH-lusks) are animals with a soft, unsegmented body that may or may not have a shell. Algae (AL-jee) are plantlike growths that live in water and have no true roots, stems, or leaves. Parasites (PAIR-uh-sites) are animals or plants that live on other animals or plants without helping them and often harming them.

BEHAVIOR AND REPRODUCTION

Some cichlids form pairs in which both parents guard eggs laid on the bottom. Some change sex. Some cichlids are mouth brooders, meaning the eggs and young develop inside the mouth of one or both parents. Many cichlids build huge, cone-shaped sand nests, sometimes in groups as large as fifty thousand stretched over several miles (kilometers) of sand.

Surfperches give birth to live young. Damselfishes, wrasses, parrotfishes, and rock whitings change colors and sexes according to life stage. Damselfishes are territorial of their mating sites and viciously attack intruders. Rock whitings change sex from female to male and live in small groups of one male and several females. Females lay their eggs directly into a plankton mass.

CICHLIDS, SURFPERCHES, THEIR RELATIVES, AND PEOPLE

Cichlids and surfperches are caught or farmed for food. Cichlids, damselfishes, wrasses, parrotfishes, and rock whitings are used in aquariums.

FISH WASH

Cleaner wrasses set up sites for providing cleaning services to other fishes. Fish come to the cleaning stations and announce their desire to be cleaned by moving their mouths or bodies. The cleaner wrasses strike a deal by brushing the "customer" with their fins, and the cleaning begins. The wrasses pick over the body, fins, and head of the customer and may even enter the gill chamber and mouth to remove parasites, mucus, dead skin, loose scales, and other waste. Both the customer and the wrasse benefit from the arrangement: The cleaner is fed, and the customer is cleaned.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists forty-two species of cichlids, surfperches, damselfishes, wrasses, parrotfishes, and rock whitings as Extinct, five as Extinct in the Wild, thirty-seven as Critically Endangered, twelve as Endangered, forty-three as Vulnerable, and one as Conservation Dependent. Extinct means no longer in existence. Extinct in the Wild means no longer alive except in captivity or through the aid of humans. Critically Endangered means facing an extremely high risk of extinction in the wild. Endangered means facing a very high risk of extinction in the wild. Vulnerable means facing a high risk of extinction in the wild. Conservation Dependent means if the conservation program were to end, the animal would be placed in one of the threatened categories.

BLUESTREAK CLEANER WRASSE (Labroides dimidiatus): SPECIES ACCOUNTS

Physical characteristics: Bluestreak cleaner wrasses are about 4½ inches (12 centimeters) long. Adults are mostly light blue. A long black stripe along each side of the body widens as it approaches the tail. The young are black with a blue stripe on the back.

Geographic range: Bluestreak cleaner wrasses live in the Indian and Pacific oceans.

Habitat: Bluestreak cleaner wrasses live on coral reefs.

Diet: Bluestreak cleaner wrasses eat what they find on other fishes.

Behavior and reproduction: Bluestreak cleaner wrasses clean other fishes. They sometimes lives in pairs but frequently live in groups of one male and six to ten females. If the male leaves the group, one of the females takes his place and in about two weeks starts functioning as a male.

Bluestreak cleaner wrasses and people: Bluestreak cleaner wrasses are common aquarium fish.

Conservation status: Bluestreak cleaner wrasses are not threatened or endangered. ∎

STRIPED PARROTFISH (Scarus iseri): SPECIES ACCOUNTS

Physical characteristics: Striped parrotfish reach a length of about 14 inches (35 centimeters). In their first phase of life, these fish have dark stripes extending from head to tail. The most prominent stripe goes through the eye and nearly to the tail. Males in the final life stage are turquoise.

Geographic range: Striped parrotfish live in the eastern part of the Atlantic Ocean from Florida to Brazil.

Habitat: Striped parrotfish live on reefs.

Diet: Striped parrotfish eat algae, which they scrape from rocks and other surfaces.

Behavior and reproduction: Parrotfish prepare for sleep by making a tube of mostly clear mucus that surrounds the body. The tube forms in about thirty to sixty minutes. The mucus tube hides the parrotfish from predators and may be an unpleasant-tasting barrier. Striped parrotfish form schools. They also change sex from female to male. These fish mate year-round in pairs or in groups, scattering their eggs, which float in open water.

Striped parrotfish and people: Striped parrotfish sometimes are fished and sold for food and sometimes are used in aquariums.

Conservation status: Striped parrotfish are not threatened or endangered. ∎

FRESHWATER ANGELFISH (Pterophyllum scalare): SPECIES ACCOUNTS

Physical characteristics: Freshwater angelfish are about 3 inches (7.5 centimeters) long. The combination of large triangular dorsal and anal fins above and below a round body gives the fish a diamond-shaped profile. The body is very narrow from side to side. Adults are silver with four dark stripes that extend from the top to the belly of the fish. The young have seven dark bars.

Geographic range: Freshwater angelfish live in South America.

Habitat: Freshwater angelfish live in lakes, swamps, and flooded forests with dense plant life and little current.

Diet: Freshwater angelfish eat bottom-dwelling crustaceans, such as shrimp.

Behavior and reproduction: Freshwater angelfish are peaceful fishes that hide in plants. They form pairs for mating. Females spawn on thick leaves, and both parents care for the eggs and young.

Freshwater angelfish and people: Freshwater angelfish are extremely popular for aquariums. Millions are sold every year.

Conservation status: Freshwater angelfish are not threatened or endangered. ∎

FOR MORE INFORMATION

Books:

Gilbert, Carter Rowell, and James D. Williams. National Audubon Society Field Guide to Fishes: North America. New York: Knopf, 2002.

Web sites:

Coleman, Ron. "Introducing the Cichlids." Cichlid Research Home Page. http://www.cichlidresearch.com/introducingcichlids.html (accessed on October 26, 2004).

Smith, Richard. "Cleaner Wrasse." Catalyst—ABC TV Science.http://www.abc.net.au/catalyst/default.htm (accessed on October 27, 2004).