Portal:Marine life/Selected Article/August, 2006
The Clownfish, or Anemonefish, are the subfamily Amphiprioninae of the family Pomacentridae. There are currently 27 species, of which one is in the genus premnas and the rest are in the subfamily's type genus Amphiprion. The other pomacentrids are called damselfish.
Clownfish are native to wide ranges of the warm waters of the Pacific; some species ranges overlap others. Clownfish are not found in the Atlantic Ocean. Clownfish live in a mutual relationship with sea anemones, or in some case settle in some varieties of soft corals, or large polyp stony corals. Once an anemone or coral has been adopted, the clownfish will defend it vigorously.
However, clownfish in an aquarium environment can exist very well without an anemone (this may be advisable as most anemones are extremely difficult to keep alive even for experienced aquarists). The anemone is required in nature because reef life is dangerous for small, brightly coloured fish with very poor swimming abilities; in an aquarium lacking predators it is not needed. For this reason, clownfish never stray far from their host. In an aquarium, where they don't have to forage for food, it is very common for clownfish to remain within 6–12 inches of their host for an entire lifetime.
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