The family Polypteridae (larger group Cladistia, Polypteriformes) consists of the most primitive Actinopterygians (ray-finned fishes), the bichirs and ropefish. All members of Polypteridae are found in Africa. Members of this group are characterized by numerous dorsal finlets (number varies with species), lobe-supported pectoral fins, and ganoid scales (similar in appearance to those of the gars).
Polypterids have two lungs and are obligate air-breathers. Young polypterids possess external gills which are lost as the fish matures.
The ropefish (also known as reedfish, Erpetoichthyes calabaricus) differs from Polypterus spp. in its lack of pelvic fins and much more elongate body.
The family Polypteridae consists of approximately 13 distinct species, with several species further identified by subspecies (e.g. Polypterus palmas, P. bichir, and P. endlicheri). Members of Polypterus are commonly classified* by jaw protrusion (“upper jaw” or “lower jaw”) as listed below:
Polypterus palmas polli
Polypterus palmas buettikoferi
Polypterus palmas palmas**
Polypterus bichir lapradei
Polypterus bichir bichir
Polypterus endlicheri endlicheri
Polypterus endlicheri congicus
*color grouping based on recent molecular phylogeny by Suzuki et al. (2010).
**estimated placement of species.