wrasse

[ras]

wrasse, common name for a member of the large family Labridae, brilliantly colored fishes found among rocks and kelp in tropical seas. Wrasses, related to the parrotfishes, feed on mollusks and are equipped with shell-crushing teeth in both the mouth and throat. The lips are fleshy, and some wrasses are able to extend the mouth and jaws forward to engulf their prey. Well known on the N Atlantic coast are the cunners (about 1 ft/30 cm long), which are useful scavengers. The tautog, or blackfish, an important food fish of the S New England coast, is a sluggish fish that hibernates in cold weather. Southern wrasses, found off the West Indies and Florida coasts, include the hogfish, a large, showy red fish with a piglike snout, and the puddingwife. The California redfish, or Pacific sheepshead, is a large wrasse reaching up to 3 ft (91 cm) and 30 lb (13.5 kg) and most abundant S of Monterey. The female is a dull red and the male is boldly patterned in crimson and black. The flesh of wrasses is sometimes poisonous to human consumers. Most wrasses belong to the genus Labrus. Wrasses are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, family Labridae.

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wrasse

Any of some 300 species (family Labridae) of slender, often brilliantly coloured, fishes, found worldwide in tropical and temperate seas, often on coral reefs. Species range from 2 in. (5 cm) to 7 ft (2 m) long. Wrasses have thick lips, large scales, long fins, and large, often protruding, canine teeth. Most eat invertebrates; some species, called cleaner wrasses, pick off and eat the external parasites of larger fishes. The tautaug (Tautoga onitis) is an edible species.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.

Wrasse

The wrasses are a family, Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with about 500 species in 60 genera.

Distribution

Wrasses are exclusively marine in distribution. They are found in the Atlantic, Indian, and Pacific Oceans, usually in shallow water habitats such as coral reefs and rocky shores where they live close to the substrate.

Anatomy

Wrasses have protractile mouths, usually with separate jaw teeth that jut outwards. The dorsal fin has 8–21 spines and 6–21 soft rays, usually running most of the length of the back. Wrasse are typically brightly coloured and sexually dimorphic. Many species are capable of changing sex: juveniles are a mix of males and females (known as Initial Phase or IP individuals) but the largest adults becoming territory-holding (Terminal Phase or TP) males.

Cleaner wrasse

Some wrasses are widely known for their role as symbiotic fish, similar to the actions and those ascribed to the Egyptian plover: other fish will congregate at wrasse cleaning stations and wait for wrasses to swim into their open mouths and gill cavities to have gnathiid parasites removed. The cleaner wrasses are best known for feeding on dead tissue and scales and ectoparasites, although they are also known to 'cheat' through the removal of healthy tissue and mucus, which is costly for the client fish to produce. The bluestreak cleaner wrasse, Labroides dimidiatus is one of the most common cleaners found on tropical reefs. Few cleaner wrasses have been observed being eaten by predators, possibly because the removal of parasites from the predator fish is more important for the survival of the predator than the short-term gain of eating the cleaner (see Trivers, R. L. 1971).

Other species of wrasse, rather than having fixed cleaning stations, specialize in making "house calls"—that is, their "clientele" are those fish that are too territorial or shy to go to a cleaning station.

Significance to humans

Wrasse are utilised as food in many parts of the world. In the western Atlantic, the most commonly eaten is the tautog. Wrasse are widely kept in both public and home aquaria, with some species being small enough to be considered reef safe.