Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Actinopterygii Osteoglossiformes Notopteridae

Scientific Name: Xenomystus nigri
Species Authority: (Günther, 1868)
Regional Assessments:
Common Name(s):
English African knifefish, African knife fish, African knife-fish, African knifefish (FB), False featherback
French Poisson couteau
Notopterus nigri Günther, 1868
Notopterus nili Steindachner, 1881

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2010
Date Assessed: 2009-05-01
Assessor(s): Getahun, A., Lalèyè, P., Moelants, T. & Olaosebikan, B.D.
Reviewer(s): Snoeks, J., Tweddle, D., Getahun, A., Lalèyè, P., Paugy, D., Zaiss, R., Fishar, M.R.A & Brooks, E.
This species has a wide distribution, with no known major widespread threats. It is therefore listed as Least Concern. It has also been assessed regionally as Least Concern for central and western Africa. More information is needed on the distribution and status of this species within north eastern Africa before an assessment can be made, and it is therefore listed as Data Deficient.

Geographic Range [top]

Range Description:This species has a scattered distribution from Sierra Leone to Angola and Sudan.

Central Africa: Xenomystus nigrii is known from Pool Malebo (Stanley Pool) and from the Lower and Central Congo River basin. It has also been recorded from just upstream Kisangani. It is known from the Lower Guinea region where it occurs in the Wouri River, Cameroon and in the Ogowe River and coastal drainages in Gabon.

Northeast Africa: It is present in the Bahr el Jebel system, Sudan.

Western Africa:Within Western Africa, Xenomystus nigri has been reported from Sierra Leone (Lake Kwarko Krim and River Gbap), Liberia (Farmington Lake), Togo (Togble-Kope River, Kelegougan flood plain), and from Benin to Nigeria and the Chad basin.
Countries occurrence:
Angola (Angola, Angola, Cabinda); Benin; Cameroon; Central African Republic; Chad; Congo; Congo, The Democratic Republic of the; Equatorial Guinea; Gabon; Liberia; Nigeria; Sierra Leone; Sudan; Togo
FAO Marine Fishing Areas:
Atlantic – eastern central
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:No information available.
Current Population Trend:Unknown
Additional data:
Population severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:A demersal species, it prefers quiet waters rich in vegetation in streams and lakes. It is a predator feeding on invertebrates. Has a modified airbreathing organ so can survive in polluted or deoxygenated conditions. Can produce barking sounds. Comes to the surface from time to time to swallow air. Feeds at dusk and during the night on worms, crustaceans, insects and snails (Mills and Vevers 1989). Although this fish, with its reduced pelvic fins, long anal fin and loss of dorsal fin superficially resembles gymnotiform electric fishes of South America, it does not have any specializations for generation of electric currents in water. Nevertheless, Xenomystus does possess electroreceptors of the ampullary type which it apparently uses for sensing prey (Braford 1982).

Use and Trade [top]

Use and Trade: It has commercial importance as an aquarium fish.

Threats [top]

Major Threat(s): This is a hardy species, but it does have commercial importance as an aquarium fish.

Conservation Actions [top]

Conservation Actions: None known.

Classifications [top]

5. Wetlands (inland) -> 5.1. Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls)
suitability: Suitable  
5. Wetlands (inland) -> 5.2. Wetlands (inland) - Seasonal/Intermittent/Irregular Rivers/Streams/Creeks
suitability: Suitable  
5. Wetlands (inland) -> 5.4. Wetlands (inland) - Bogs, Marshes, Swamps, Fens, Peatlands
suitability: Suitable  
5. Wetlands (inland) -> 5.5. Wetlands (inland) - Permanent Freshwater Lakes (over 8ha)
suitability: Suitable  
5. Wetlands (inland) -> 5.7. Wetlands (inland) - Permanent Freshwater Marshes/Pools (under 8ha)
suitability: Suitable  
5. Wetlands (inland) -> 5.8. Wetlands (inland) - Seasonal/Intermittent Freshwater Marshes/Pools (under 8ha)
suitability: Marginal  

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
In-Place Species Management
In-Place Education
5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.1. Intentional use: (subsistence/small scale)
♦ timing: Ongoing    
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

♦  Food - human
 Local : ✓ 

♦  Pets/display animals, horticulture
 National : ✓ 

Bibliography [top]

Pan-Africa freshwater assessment references. Currently, full citations for references used in the Pan-Africa biodiversity assessments are unavailable on the Red List web site. These will be added to the site in 2011. We apologise for any inconvenience this causes.

IUCN. 2010. IUCN Red List of Threatened Species (ver. 2010.3). Available at: (Accessed: 2 September 2010).

Citation: Getahun, A., Lalèyè, P., Moelants, T. & Olaosebikan, B.D. 2010. Xenomystus nigri. In: The IUCN Red List of Threatened Species 2010: e.T182400A7878379. . Downloaded on 13 October 2015.
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