You can sponsor this page

Heterotis niloticus (Cuvier, 1829)

African bonytongue
Upload your photos and videos
Pictures | Stamps, coins, misc. | Google image
Image of Heterotis niloticus (African bonytongue)
Heterotis niloticus
Picture by Katemo Manda, B.


Benin country information

Common names: [No common name]
Occurrence: native
Salinity: freshwater
Abundance: abundant (always seen in some numbers) | Ref: Gras, R., 1961
Importance: | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: live export: yes;
Comments: Known from Lake Nokoue (Ref. 3019, 48864), Lake Aheme (Ref. 48864), Lagoon Toho-Todougba (Ref. 46973) and Lake Ahouangan (Ref. 46973). Also Ref. 3000, 28663, 43836, 48865, 50673.
National Checklist:
Country Information: https://www.cia.gov/library/publications/resources/the-world-factbook/geos/bn.html
National Fisheries Authority:
Occurrences: Occurrences Point map
Main Ref: Adite, A. and R. van Thielen, 1995
National Database:

Common names from other countries

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Teleostei (teleosts) > Osteoglossiformes (Bony tongues) > Arapaimidae (Bonytongues)
Etymology: Heterotis: Greek, heteros = other + Greek, ous, otis = ear (Ref. 45335);  niloticus: Named after M. Ehrenberg, scientist (Ref. 50686).
  More on author: Cuvier.

Environment: milieu / climate zone / depth range / distribution range Ecology

Freshwater; pelagic; depth range 1 - ? m (Ref. 13851).   Tropical; 25°C - 30°C (Ref. 2060); 16°N - 3°N, 17°W - 37°E

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

Africa: native in all basins of the Sahelo-Sudanese region, the Senegal, Gambia, Corubal, Volta, Ouémé, Niger, Bénoue, Chad and Nile basins and Lake Turkana (Ref. 2920, 3012, 3514). Successful introductions in the storage reservoirs of Côte d'Ivoire, Cross, Sanaga, Nyong and Ogowe rivers and the lower and middle Congo basin, including Ubangui and Kasaï (Ref. 2920); rapidly enlarged its distribution in the Lualaba, upper Congo basin, after extraordinary inundations in 1979 (Ref. 51906). Also introduced in Madagascar (Ref. 3514, 13333). Several countries report adverse ecological impact after introduction.

Length at first maturity / Size / Weight / Age

Maturity: Lm 40.0, range 40 - 40 cm
Max length : 100.0 cm SL male/unsexed; (Ref. 31256); max. published weight: 10.2 kg (Ref. 2920)

Short description Identification keys | Morphology | Morphometrics

Dorsal spines (total): 0; Dorsal soft rays (total): 32 - 37; Anal spines: 0; Anal soft rays: 34 - 39; Vertebrae: 66 - 69. Elongated and robust body, its height 3.5-5 times in SL (Ref. 2920). Relatively short head, its length 3.5-5 times in standard length (Ref. 2920, 5156). Dermal bones of cranium deeply carved by large sensory pits (Ref. 1878, 2920). Lips thick; dermal flap on border of gill cover (Ref. 13851). Teeth conical (Ref. 5156). Dorsal and anal fins spineless, elongated and posteriorly positioned, ending close to the small, rounded caudal fin (Ref. 3032, 13851, 28714, 30488). Caudal peduncle very short (Ref. 2756, 3054, 3069). Scales strong, thick, large (Ref. 28714, 30488), oval, with exposed portion thick and corrugated, with a more or less vermiform sculpture (Ref. 53264). 34-40 lateral-line scales, 2.5/6 scales on lateral side of body before pelvic fin, 5-6 scales between dorsal and anal fin (Ref. 367, 2756, 2920, 5156). Lateral line a straight line from above operculum to middle of caudal peduncle (Ref. 1878). Number of gill rakers increases with size: 33 (young) to 98 on ceratobranchial and 21 (young) to 76 on epibranchial (Ref. 2920). Young specimens with external gills (Ref. 30488). Coloration a uniform gray, brown or bronze (Ref. 2920), darker during period of reproduction (Ref. 367). Young specimens often with dark longitudinal bands and scales with an oval spot in posterior zone of anal and dorsal fins (Ref. 2920).

Biology     Glossary (e.g. epibenthic)

Obligate air-breathing (Ref. 126274); Obligate air-breathing (Ref. 126274), able to survive in deoxygenated waters; the hardiness of this fish, together with its great growth rate make it a candidate for aquaculture in Africa and it has been transported to a number of countries for this purpose (Ref. 1739, 50623). Escapees from ponds into the wild resulted in established populations, which form the basis for fisheries (Ref. 1739). Maximum observed length in Lake Kainji: 100 cm, observed weight: 10000 g (Ref. 3034, 3799). Young found in swampy places among aquatic vegetation (Ref. 5156, 30488). Adults live in open water of rivers and lakes, in both the pelagic and littoral zone (Ref. 5156). Feeds on mud (Ref. 6160, 28714), phytoplankton (Ref. 3023, 28714, 31256), vegetable debris and small invertebrates (Ref. 28714). The only plankton-feeder of the Osteoglossidae (Ref. 13851). Suprabranchial organ has a sensory function and a mechanic function in concentrating little food particles (Ref. 3012, 50624). During breeding, mature adults create a circular nest in swamps (Ref. 13851, 26281, 41544). Young leave the nest after a few days and are guarded by the male (Ref. 26281).

Life cycle and mating behavior Maturities | Reproduction | Spawnings | Egg(s) | Fecundities | Larvae

Breeds in the wet season in swamps and floodplains (Ref. 28714), building a circular nest about 1 m in diameter and 20 to 60 cm deep (Ref. 26281). The rim of the nest is a high wall formed out of plant chunks, about 15-20 cm thick and projecting above the water surface; the bottom is a clean platform of clay or mud; after spawning the fish leave by way of a hole in the wall through which, 5 days later, the young leave the nest and are guarded by the male (Ref. 26281). Also Ref. 3074, 10609, 36900.

Main reference Upload your references | References | Coordinator | Collaborators

Paugy, D., 1990. Osteoglossidae. p. 114-115. In C. Lévêque, D. Paugy and G.G. Teugels (eds.) Faune des poissons d'eaux douces et saumâtres de l'Afrique de l'Ouest. Tome 1. Coll. Faune Trop. n°XXVIII. Musée Royal de l'Afrique Centrale, Tervuren and Éditions de l'ORSTOM, Paris. 384 p. (Ref. 2920)

IUCN Red List Status (Ref. 130435)

  Least Concern (LC) ; Date assessed: 14 August 2019

CITES (Ref. 128078)

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Potential pest (Ref. 40814)




Human uses

Fisheries: commercial; aquaculture: commercial; aquarium: commercial
FAO(Aquaculture systems: production; ; publication : search) | FishSource |

More information

Trophic ecology
Food items
Diet compositions
Food consumptions
Food rations
Predators
Ecology
Ecology
Home ranges
Population dynamics
Growths
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversions
Recruitments
Abundances
Life cycle
Reproduction
Maturities
Fecundities
Spawnings
Spawning aggregations
Egg(s)
Egg developments
Larvae
Larval dynamics
Anatomy
Gill areas
Brains
Otoliths
Physiology
Body compositions
Nutrients
Oxygen consumptions
Swimming type
Swimming speeds
Visual pigment(s)
Fish sounds
Diseases / Parasites
Toxicities (LC50s)
Genetics
Genetics
Electrophoreses
Heritabilities
Human related
Aquaculture systems
Aquaculture profiles
Strains
Ciguatera cases
Stamps, coins, misc.
Outreach
Collaborators
References
References

Tools

Special reports

Download XML

Internet sources

Estimates based on models

Phylogenetic diversity index (Ref. 82804):  PD50 = 1.0312   [Uniqueness, from 0.5 = low to 2.0 = high].
Trophic level (Ref. 69278):  2.7   ±0.1 se; based on diet studies.
Resilience (Ref. 120179):  Medium, minimum population doubling time 1.4 - 4.4 years (K=0.22-0.4; Fec > 1,000).
Fishing Vulnerability (Ref. 59153):  Moderate to high vulnerability (55 of 100).
Price category (Ref. 80766):   Unknown.