We have chosen to present here two very close families, the Balistidae (triggerfish) and the Monacanthidae (filefish). Species of these two families have in common a compressed body, an erectile spine above their head, and a very characteristic diamond shape.
Triggerfish and filefish are hard to confuse with other reef fish. Their massive diamond-shaped body is easy to identify, and their colorful geometric patterns make some of them emblematic in the tropical seas. There are 40 triggerfish and more than 100 filefish species in the world. Some of them appreciate the shallow waters of the lagoons and are easy to see while snorkeling. Triggerfish are named after the erectile dorsal fin that they draw when threatened, but they are generally inquisitive and don’t hesitate to come close to swimmers. During mating season, triggerfish can get aggressive while keeping their nests and sometimes bite intruders, some of them being snorkelers. The titan triggerfish, sometimes 70 cm long, is famous for its dreadful bites. Filefish are more peaceful.
The most famous triggerfish undoubtedly is the lagoon triggerfish (or Picasso triggerfish). It is widespread in tropical seas of the Indian and Pacific Oceans. It can notably be seen in lagoons, even in shallow areas. It looks like its white and yellow stripes have been hand-painted onto its faded black body. One of its cousins, the reef triggerfish, has been chosen as an emblem to the Hawaii State, where it is locally known as Humuhumunukunukuapua’a. But it’s not endemic to the archipelago: the reef triggerfish occurs from the Eastern African Coasts to French Polynesia. If we had to give an award to the most fanciful scales pattern, it would be to the clown triggerfish with its white circles in contrast to a black body and its bright yellow lips. The Arabian picassofish, with its fluorescent-blue rimmed eyes, can exclusively be seen in the Red Sea and only 6 triggerfish species live in the Caribbean Sea.
The most common filefish is the scrawled filefish, with a circumtropical distribution. In the Caribbean, two species are particularly easy to see: the white-spotted filefish and the Caribbean orange-spotted filefish. The prettiest filefish may be the orange-spotted filefish, adorned with a superb turquoise and golden robe, which occurs from East Africa to Melanesia.
Arabian Picasso triggerfish
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