Triggerfish

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{{Taxobox | color = pink | name = Triggerfish | image = Titan_triggerfish.jpg | image_width = 250px | image_caption = Titan Triggerfish (Balistoides viridescens) | regnum = Animalia | phylum = Chordata | classis = Actinopterygii | ordo = Tetraodontiformes | familia = Balistidae | subdivision_ranks = Genera | subdivision = See text. }}

Triggerfishes are the brightly coloured fishes of the family Balistidae.

Marked by lines and spots, they inhabit warm coastal waters of the Atlantic, Mediterranean and the Indo-Pacific.

Their size varies from 30 cm (1 foot) to 75 cm (2.5 feet). Most are solitary and diurnal. They feed on hard-shelled invertebrates, a few feed on large zooplankton or algae. They lay their demersal eggs in a small hole, dug in the ground. Some species guard their eggs.

Triggerfish have a roundish, laterally flat body with an anterior dorsal fin. They can erect the first two dorsal spines, the first one locks and the second one unlocks. This prevents predators from swallowing them or pulling them out of their holes. This locking and unlocking behaviour is why they are named 'Triggerfish'.

They have a small pectoral fin, fused to one spine. Their small eyes, situated on top of their big head, can be rotated independently. They have tough skin, covered with rough rhomboid-shaped scales that form a tough armour on their body. A big, angular-shaped head extends into a snout with strong jaws and sharp teeth, made for crushing shells. Each jaw contains a row of eight teeth, while the upper jaw contains another set of six plate-like teeth.

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Behavior

A few of the triggerfish species can be quite aggressive during reproduction season. In particular Picasso triggerfish and Titan triggerfish viciously defend their circular nests against any intruders, including scuba divers and snorkelers. The Picasso triggerfish is relatively small, but due to its large size and powerful teeth the Titan triggerfish poses a serious threat to inattentative divers.

Image:Picasso.triggerfish.arp.jpg Image:Redtoothed triggerfish2.jpg Image:Titan Triggerfish.jpg Image:Orange-lined Triggerfish.jpg.

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Genera

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References

Template:Commonscatde:Drückerfische fr:Balistidae it:Balistidae lt:Raguotinės

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