The Arapaima is a tropical fish of the Amazon basin. It is one of the largest freshwater fish in the world. Arapaima reach sizes of up to 15 feet in length. The scales are olive-green, turning increasingly reddish towards the tail region.
The swim bladder is open to the pharynx and the arapaima uses the bladder which is rich in blood vessels as a lung. Arapaima feed mainly on fish. The picture above comes from a public aquarium.
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