Polypteridae

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Polypteridae (bichir; subclass Brachiopterygii, order Polypteriformes) A small family of freshwater fish that have an elongate body, the skin covered with ganoid scales and, typically, a dorsal fin consisting of a series of separate finlets each with its own stiff ray. The pectoral fins consist of a fleshy stalk bearing a fanlike fin. Bichirs can use the modified swimbladder as a lung. Polypterus bichir (Nile bichir), 70 cm, has about 15 dorsal finlets. It is a carnivorous fish often found along the weedy edges of lakes and rivers. In addition to the 11 extant species a number of fossil species are known. They occur in Africa.