Actinopterygii (ray-finned fishes) > Polypteriformes
(Bichirs) > Polypteridae
Etymology: Polypterus: Greek, poly = a lot of + Greek, pteron = wing, fin (Ref. 45335); senegalus: Named after M. d'Arnaud, collector of the two specimens (Ref. 1688).
Environment / Climate / Range
Freshwater; demersal; pH range: 6.0 - 8.0; dH range: 5 - 19; potamodromous (Ref. 51243). Tropical; 25°C - 28°C (Ref. 2060)
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 15 - 23 cm
Max length : 70.0 cm SL male/unsexed; (Ref. 3188); max. published weight: 207.00 g (Ref. 3013)
(total): 8 - 11;
Vertebrae: 53 - 59. Diagnosis: Polypterus senegalus is characterized by jaws of equal length or an upper jaw slightly longer than lower jaw and a pectoral fin not reaching the first dorsal ray (Ref. 2756, 2835, 42908, 43035, 81263).
Africa: The subspecies Polypterus senegalus senegalus is known from Nile River basin (Ref. 2835, 3188), Lake Turkana (Ref. 3188) and West Africa in Senegal, Gambia, Niger, Volta and Chad basins (Ref. 2835, 3188, 81263). The subspecies Polypterus senegalus meridionalis is known from Congo River, from the Upper Lualaba River downstream to Yangambi (Ref. 2835, 3188, 4910, 45434).
This species inhabits marginal swamps and freshwater lagoons (Ref. 3066) and it appears to favor sheltered inshore habitats (Ref. 3034); it inhabits the muddy regions at the sides of rivers and swampy waters, where it lies quiet or glides about with snake-like movements (Ref. 49805). During the hottest hours of the day, it comes to the surface just on the outer edge of the vegetation, and it goes back to the bottom when disturbed (Ref. 45962). It feeds on insects, crustaceans, mollusks, frogs and fishes (Ref. 4903, Ref. 28714). Polypterus senegalus senegalus is mainly insectivorous (Ref. 367). Longevity of Polypterus senegalus in captivity can be 34 years and more (Ref. 48954).
Larval fish 1.1-3.8 cm SL were found in papyrus root mat and juveniles up to 10 cm SL retaining external gills were found in fringing water hyacinth. Feeds mainly on fishes (Ref. 9695), insects, crustaceans, mollusks, frogs as well as on plant fragments and seeds.
In Polypterus senegalus courtship starts with a series of leaps from the surface by usually only one of the pair at a time, followed by a slow descent through the water. After a while the male stays very close to the female and at times the female will remain motionless in the water and the male will come up to her from behind and nudge her with sidewise movements of his head. The enlarged and swollen anal fin of the male is folded in a cup-like fashion and is used to brush the female (Ref. 42791). No nest is constructed, but the eggs are laid a few at a time throughout the thick vegetation (Ref. 42791). The larvae, which move about with the male parent in a dense school, are provided with accessory gills and appear very salamander-like (Ref. 42791).
Gosse, J.P. and J. Daget, 2003. Polypteridae. p. 101-112. In D. Paugy, C. Lévêque and G.G Teugels (eds.) The fresh and brackish water fishes of West Africa Volume 1. Coll. faune et flore tropicales 40. Institut de recherche de développement, Paris, France, Muséum national d'histoire naturelle, Paris, France and Musée royal de l'Afrique Central, Tervuren, Belgium, 457p. (Ref. 81263)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5002 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00537 (0.00305 - 0.00944), b=3.00 (2.84 - 3.16), based on LWR estimates for species & (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.5 ±0.2 se; Based on diet studies.
Resilience (Ref. 69278
): Very Low, minimum population doubling time more than 14 years (tmax=34; Fec < 1,000).
Vulnerability (Ref. 59153
): Moderate to high vulnerability (50 of 100) .