Actinopterygii (ray-finned fishes) > Osteoglossiformes
(Bony tongues) > Mormyridae
Etymology: Marcusenius: Becasue of J. Marcusen, author of "Zur Phauna des Schwarzen Meeres", 1867; ichthyologist. More on author: Peters.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal; pH range: 7.0 - ? ; dH range: 10 - ?; potamodromous (Ref. 51243). Tropical; 22°C - 24°C (Ref. 12468); 20°S - 31°S
Africa: Lower Zambezi River from the delta upstream to at least Tete, if not Victoria Falls, and the lower Shire River; also Pungwe, Buzi and Mulela Rivers (Ref. 75962). Also upper and central Congo basin (Ref. 3203, 95585), Lake Rukwa basin (Ref. 95585), and east flowing rivers of Tanzania and Natal (Ref. 3203). Widespread and common in the Cunene and Okavango systems (Ref. 7248). Reports from Pool Malebo (Ref. 41585), the middle Congo River (Ref. 4910) and the Lulua (Kasai drainage)(Ref. 42554) possibly refer to M. angolensis.
Length at first maturity / Size / Weight / Age
Maturity: Lm 13.0  range ? - ? cm
Max length : 32.0 cm TL male/unsexed; (Ref. 27292); max. published weight: 500.00 g (Ref. 7248)
Morphology | Morphometrics
soft rays: 26 - 31. Diagnosis: Marcusenius macrolepidotus is best distinguished from M. altisambesi by the number of circumpeduncular scales, which is 12-18 vs. 12-14, and an electric organ discharge lacking an initial head-negativity; from M. devosi by the number of scales in linear series along the lateral line row, which is 52-62 vs. 56-66, shorter caudal peduncle length, and weaker Namp of its electric organ discharge; from M. pongolensis by the number of scales in linear series along the lateral line row, which is 52-62 vs. 70-76, the umber of circumpeduncular scales, which is 12-18 vs. 16-20, a greater body depth, and longer Ndur of its electric organ discharge in females and juveniles; and from M. angolensis by its lower number of anal fin rays, being less than 31 vs. 33, and dorsal fin rays, being less than 24 vs. 26, and a higher number of circumpeduncular scales (Ref. 75962).
Caught with dipnets in the Kafue floodplain, Zambia. Prefers well-vegetated, muddy bottomed marginal habitats of rivers and floodplains. A shoaling species which moves inshore after dark. Migrates within rivers. Recorded to move up tributaries in shoals during flood season (Ref. 13337). Feeds on invertebrates, especially midge and mayfly larvae and pupae taken from the bottom and off plant stems. Breeds during the rainy season in shallow vegetated localities; females carry up to 6,000 eggs (Ref. 7248). Possesses electroreceptors over the entire head and on the ventral and dorsal regions of the body, but absent from the side and the caudal peduncle where the electric organ is located (Ref. 10011).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Gosse, J.-P., 1984. Mormyridae. p. 63-122. In J. Daget, J.-P. Gosse and D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ORSTOM, Paris and MRAC, Tervuren. Vol. 1. (Ref. 3203)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 118484)
Threat to humans
Gamefish: yes; aquarium: commercial
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01318 (0.00767 - 0.02266), b=2.89 (2.75 - 3.03), in cm total length, based on LWR estimates for this species & Genus-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.2 ±0.2 se; based on diet studies.
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (K=0.7-1.1).
Vulnerability (Ref. 59153
): Low vulnerability (22 of 100) .