Polypterus | 水產百科網

Genus of fishes

Polypterus is a genus of freshwater fish in the bichir family (Polypteridae) of order Polypteriformes. The type species is the Nile bichir (P. bichir). Fish in this genus live in various areas in Africa. Polypterus is the only known vertebrate to have lungs, but no trachea.

The etymology of the genus name derives from a combination of the Greek prefix πολυ-, poly- (many) and the root word πτερον, pteron (wing or fin) – "many fins".

In shallow water, Polypterus inhales primarily through its spiracle (blowhole). Exhalation is powered by muscles in the torso. During exhalation, the bony scales in the upper chest become indented. When the muscles are relaxed, the bony scales spring back into position, generating negative pressure within the torso, resulting in a rapid intake of air through the spiracle. The a...