triggerfish

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Triggerfish

Triggerfishes are members of the family Balistidae of the order Tetradontiformes. They derive their name from a unique feature of their dorsal fin. The trigger-fish can lock the large dorsal spine in an upright position by supporting it with its smaller secondary spine. This protects the fish from predation by larger fish because the erect spine makes the fish hard to swallow or extract from small crevices. The locked dorsal spine can be unlocked by depressing the third spine or trigger which is connected to the second spine.

A distinctive characteristic of triggerfish is similarity in size and shape of the second dorsal (back) and anal fins. The belly in front of the anal fin is the widest circumference of the fish. The body of the triggerfish is protected by bony plates.

Triggerfishes are moderately large fish generally found on coral reefs widely distributed throughout the world, in all about 37 species. The gray triggerfish, Balistes capriscus, averages under 1 ft (0.3 m) in length but may grow to 2 ft (0.6 m) with a weight of 3 lb (1.4 kg). It is found in the warm waters of the Gulf of Mexico and the Mediterranean. These grayish fish often appear spotted or splotchy when swimming in among seaweeds.

Among the largest in the family is the ocean triggerfish, Canthidermis sufflamen, which grows to 2 ft (0.6 m) and weighs about 10 lb (4.5 kg). It ranges in distribution from the coast of Florida to the Caribbean. The ocean triggerfish is capable of making sounds like some of its relatives. One of the ways it makes sound is by vibrating some muscles that are attached to its swim bladder.

Several species, such as the redtail triggerfish, are found in the western Pacific. The redtail Xanthichthys mento is a 10 in (25 cm) fish with a purplish blue color and a red tail. In contrast to the redtail triggerfish, Abalistes stellaris may grow to 24 in (60 cm) in length.

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Triggerfish

Triggerfishes are members of the family Balistidae of the order Tetradontiformes. They derive their name from a unique feature of their dorsal fin. The triggerfish can lock the large dorsal spine in an upright position by supporting it with its smaller secondary spine. This protects the fish from predation by larger fish because the erect spine makes the fish hard to swallow or extract from small crevices. The locked dorsal spine can be "un locked" by depressing the third spine or "trigger" which is connected to the second spine.

A distinctive characteristic of triggerfish is similarity in size and shape of the second dorsal (back) and anal fins. The belly in front of the anal fin is the widest circumference of the fish. The body of the triggerfish is protected by bony plates.

Triggerfishes are moderately large fish generally found on coral reefs widely distributed throughout the world, in all about 36 species . The gray triggerfish, Balistes capriscus, averages under 1 ft (0.3 m) in length but may grow to 2 ft (0.6 m) with a weight of 3 lb (1.4 kg). It is found in the warm waters of the Gulf of Mexico and the Mediterranean. These grayish fish often appear spotted or splotchy when swimming in among seaweeds.

Among the largest in the family is the ocean trigger-fish, Canthidermis sufflamen, which grows to 2 ft (0.6 m) and weighs about 10 lb (4.5 kg). It ranges in distribution from the coast of Florida to the Caribbean. The ocean triggerfish is capable of making sounds like some of its relatives. One of the ways it makes sound is by vibrating some muscles that are attached to its swim bladder.

Several species, such as the redtail triggerfish, are found in the western Pacific. The redtail Xanthichthys mento is a 10 in (25 cm) fish with a purplish blue color and a red tail. In contrast to the redtail triggerfish, the Abalistes stellaris may grow to 24 in (60 cm) in length.

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triggerfish, any of several species of tropical reef fishes with laterally compressed bodies, heavy scales, and tough skins. They are named for the mechanism of the three spines of the dorsal fin: when the fish is alarmed the first of these spines is locked upright by the second and drops only when the latter is pressed like a trigger. The function of this reaction is to lock the fish firmly in a mass of coral; when attacked, the fish dives into the coral and erects the spine, releasing it only when the danger has passed. Triggerfishes have powerful, chisellike teeth adapted for cracking the coral and mollusks on which they feed. They average 1 lb (0.45 kg) in weight and 1 ft (30 cm) in length and are common around the West Indies and Florida. The gray, or common, triggerfish is variably colored in mottled browns, yellows, or grays, but many other species are strikingly colored, e.g., the queen triggerfish in blue, green, and yellow. The ocean triggerfish, which unlike most triggerfishes found in waters away from reefs, among seaweed or debris; it is up to 2 ft (60 cm) long and may weigh as much as 13 lb (6 kg). Triggerfish are classified in the phylum Chordata, subphylum Vertebrata, class Actinopterygii, order Tetraodontiformes, family Balistidae.

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trig·ger·fish / ˈtrigərˌfish/ • n. (pl. same or -fishes) a marine fish (family Balistidae: numerous genera and species) occurring chiefly in tropical inshore waters. It has a large, stout dorsal spine that can be erected and locked into place, allowing the fish to wedge itself into crevices.

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triggerfish Any of several tropical marine fish found in warm, shallow Pacific waters, identified by a dorsal fin spine that can be erected to lodge the fish in a coral cavity, as a protection against predators. Length: to 60cm (24in). Family Balistidae; typical genus Balistoides.

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triggerfish See BALISTIDAE.