English: Bichirs; Reedfish; Dragon bichir; Dragon fin.
Genera: 2; ± 14 species; 1 family, Polypteridae.
Region: Africa; Nile River system.
Habitat: tropical freshwater; mainly swampy, shallow floodplains, estuaries.
Use: popular in public and large hobby aquaria.
ZoologyFish; eel like; archaic-looking; dragon-like appearance; nocturnal; elongated; jaw structure resembles that of the tetrapods than that of the teleost fishes; they have a pair of primitive slit-like spiracles on the top of their heads, facultatively used to breathe air; two gular plates, and paired ventral lungs, their lungs are smooth sacs instead of alveolated tissue.
Gills: 4 pairs of gill arches.
Fins: unique series of 7 to 18 dorsal finlets, each has bifid, double-edged, tips, and are the only fins with spines; the rest of the fins are composed of soft rays; fleshy pectoral fins similar to those of lobe-finned fishes.
Form: body is covered in thick, bonelike, and rhombic, ganoid scales.
Size: 25 to 100 cm.
Food: small vertebrates, crustaceans, insects.
Food: predatory.
Behavior: peaceful, preferring to lie on the bottom, and make good tankmates; life expectancies up to 10 years.
TaxonomyCladistia, polypterids and their fossil relatives, are considered the sister group to all other extant ray-finned fishes, Actinopteri.