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Arapaima gigas (aka Piracuru)



One of the largest freshwater fishes in the world, the arapaima can reach a length of 9 feet or more and a weight of 440+ pounds. It is usually gray in color, with an orange speckling near the posterior end. The dorsal and anal fins are set well back near the tail. Like other members of its order, this fish has a bony (toothed) tongue, which it uses to dismember prey.

Distribution and Habitat

The arapaima inhabits a variety of freshwater habitats in the Amazon River basin, including floodplain lakes, large tributaries, and flooded forests. Its exact habitat fluctuates with the seasons; lakes and river channels are favored during the dry season, while flooded forests become much more important during the wet season. Because the waters it inhabits are oxygen-deficient, the arapaima must "come up for air" every 10-20 minutes.


Arapaima feed primainly on other fish, but will take birds or other animals that come their way. Although they prefer to hunt near the surface, they will dive for food if necessary.


Mating and egg laying occur when water levels are low, generally from February into March. The fertilized eggs are deposited into a nest (usually on a sandy bottom) that is about 20 inches across and 6 inches deep. Both parents guard and aerate the eggs until they hatch, which occurs when the water level begins to rise, usually between May and August. The female typically leaves the nest area once the young begin to hatch, leaving all responsibility for the hatchlings to the male. The male keeps the young in close proximity at all times, and will take them into his mouth whenever danger is present. He will continue to protect his young until they are large enough to fend for themselves.

Conservation Status

Because they tend to stay near the surface, arapaimas are easy targets for spear fishermen. Some indigenous communities consume the arapaima's meat and tongue and collect its large scales, which are fashioned into jewelry and other items. Although it is not known whether the total number of arapaimas in the wild has declined, there has been a noticeable decrease in the number of individuals at the maximum end of the size range (in other words, the average maximum length and weight has decreased).

Scientific Classification

phylum Chordata
subphylum Vertebrata
superclass Osteichthyes
class Actinopterygii
order Osteoglossiformes
family Osteoglossidae
genus & species Arapaima gigas

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The Robinson Library >> Science >> Zoology >> Fishes >> Class Actinopterygii

This page was last updated on March 24, 2018.