@article {668, title = {Length-weight relationships and condition factors of Mormyridae species in the Niger River: implications for conservation and management}, journal = {Limnology and Freshwater Biology }, volume = {2025}, year = {2025}, month = {Jan-01-2025}, pages = {215-221}, abstract = {

The length-weight relationship and condition factor of the ten most abundant Mormyridae species in the Niger River at Niamey were examined from August to November 2023. The species assessed were\ Mormyrus rume,\ Campylomormyrus tamandua,\ Pollimyrus isidori,\ Brienomyrus niger,\ Hyperopisus bebe, Mormyrus macrophthalmus,\ Mormyrops anguilloides,\ Brevimyrus niger,\ Mormyrops oudoti,\ Cyphomyrus Psittacus, and\ Marcusenius cyprinoides. Analysis of their length-weight relationships revealed \“b\” values ranging from 2.08 to 2.87, suggesting negative allometric growth across all species. Condition factor (k) values varied from 1.22 \± 0.31 for\ H. bebe\ to 10.48 \± 2.83 for\ M. cyprinoides, with no significant differences in average condition factors among the species. These findings highlight the potential vulnerability of Mormyridae species to environmental changes and anthropogenic pressures, emphasizing the need for targeted conservation measures. The results underscore the importance of sustainable fisheries management practices to preserve biodiversity and ensure the long-term productivity of the Niger River ecosystem. The observed negative allometric growth patterns indicate that environmental conditions may be suboptimal for these species, potentially due to factors such as habitat degradation, water quality issues, or overfishing. Addressing these challenges through habitat restoration and regulatory measures could enhance the resilience of fish populations and support sustainable fisheries.

}, keywords = {condition factor, length-weight analysis, Mormyridae, sustainable fisheries management, the Niger River}, issn = {2658-3518}, doi = {10.31951/2658-3518-2025-a-2-215}, url = {https://doi.org/10.31951/2658-3518-2025-a-2-215}, author = {Souley, S.M.N. and Harouna, M. and Ado, M.I. and Youssoufa, I.} } @article {660, title = {Diet of some fish species of the family Mormyridae (Actinopterygii: Teleostei; Bonaparte, 1831) from the upper Sanaga River, Central Region of Cameroon}, journal = {Journal of Animal Diversity}, volume = {6}, year = {2024}, month = {31 March 2024}, pages = {51-62}, chapter = {51}, abstract = {

This study was carried out between October 2020 and October 2021 with the aim of determining sustainable management options and nutrition for the domestication of Mormyridae fish species living in the Sanaga River in central Cameroon. For this purpose, 451 specimens collected from local fishermen were identified and grouped into four genera and seven species, constituting 20.84\% Campylomormyrus phantasticus (Pellegrin), 5.32\% Hippopotamyrus castor (Pappenheim), 24.61\% Mormyrops anguilloides (Linnaeus), 18.63\% Mormyrops caballus (Pellegrin), 4.66\% Mormyrops zanclirostris (G\ünther, 1867), 15.52\% Mormyrus rume (Valenciennes), and 10.42\% Mormyrus tapirus (Pappenheim). Fish were measured, and parameters were obtained after dissection using intestinal morphometric characteristics and stomach content analysis methods. The emptiness coefficient varied from 0\% (Hippopotamyrus castor and Mormyrops zanclirostris) to 26.66\% (Mormyrus rume). The relative mass of the intestine was low in all studied species; the intestinal coefficient and the Zihler index of all these species are within the range of carnivorous species. Analysis of stomach contents revealed a broad food spectrum containing twelve categories of prey. Insects, macrophytes and larval insect shelters were the preferred foods of Mormyrops anguilloides, Mormyrops caballus and Mormyrops zanclirostris, while insect larvae and larval shelters were the preferred prey for other species. Site and season had little effect on the categories of prey consumed by these species.

}, keywords = {Biodiversity, Ebebda, feeding, Monatele, Mormyridae, stomach contents}, doi = {10.22034/JAD.2024.6.1.5}, url = {http://dx.doi.org/10.22034/JAD.2024.6.1.5}, author = {Akohogni, MAM and Medjo, KE and Zebaze, TB and Chiassa, NKA and Mepa, TCP and Tiogu{\'e}, TC and Fon, ED} } @article {644, title = {Trophic ecology of the African riverine elephant fishes (Mormyridae)}, volume = {14}, year = {2024}, month = {Aug-01-2024}, abstract = {

Multiple species of the elephant fishes (Mormyridae) commonly coexist in sympatry in most African tropical rivers and lakes. In this study, we investigated the trophic ecology and potential trophic niche partitioning of eleven mormyrid fish species from the Sanaga River system in Cameroon using the stable isotope composition of carbon and nitrogen in the muscle samples. Albeit most mormyrids mainly feed on invertebrates, we found differences in isotope ratios, and we report signs of the trophic niche partitioning among species. We further found significant differences in isotopic signatures within the Mormyrus genus, suggesting ecological niche diversification among three closely related species. We have also evaluated differences in the isotopic signals between seasons in four species, which could be possibly caused by species migration and/or anthropogenic agricultural activities. To evaluate body shape, we applied geometric morphometric analyses, and we show that most of the species are clearly morphologically separated. We focused on the mormyrid ecomorphology to identify a possible interaction between shape and ecology, and we found a relationship between the \δ13C (but not \δ15N) isotopic signal and morphology, suggesting their interplay during mormyrid evolution. Overall, we present robust evidence of the trophic niche partitioning within the mormyrid species community, and we integrate trophic ecology with morphometrics, shedding light on the enigmatic evolutionary history of these fascinating African fishes.

}, keywords = {mormyrids, stable isotopes, trophic ecology, trophic position, trophic resource portioning}, issn = {2045-7758, 2045-7758}, doi = {10.1002/ece3.70173}, url = {http://dx.doi.org/10.1002/ece3.70173}, author = {Sommer, Gina Maria and Njom, Samuel Didier and Indermaur, Adrian and Nyom, Arnold Roger Bitja and Jandov{\'a}, Kate{\v r}ina and Kukla, Jaroslav and Petrt{\'y}l, Miloslav and Hork{\'a}, Petra and Musilova, Zuzana} } @inbook {633, title = {Exploration du Parc National de l{\textquoteright}Upemba Mission G.F. De Witte, Fascicule 73 Poissons}, booktitle = {Exploration du Parc National de l{\textquoteright}Upemba Mission G.F. De Witte}, volume = {73}, year = {1976}, publisher = {Fondation Pour Favoriser Les Recherches Scientifiques en Afrique}, organization = {Fondation Pour Favoriser Les Recherches Scientifiques en Afrique}, address = {Brussels}, author = {Poll, M.} } @article {cite-key, title = {Diagnosen von neuen Flussfischen aus Mossambique}, journal = {Bericht {\"u}ber die zur Bekanntmachung geeigneten Verhandlunreuss.Akademie der Wissenschaften zu Berlin}, volume = {1852}, year = {1852}, pages = {273{\textendash}276, 681{\textendash}685}, keywords = {Alestes imberi}, author = {Peters, W.} } @book {697, title = {Histoire naturelle des poissons. Histoire naturelle des poissons (Lacep{\'e}de)}, volume = {v. 5}, year = {1803}, pages = {i-lxviii + 1-803 + index, Pls. 1-21.}, url = {https://www.biodiversitylibrary.org/item/48197$\#$page/11/mode/1up}, author = {Lacep{\`e}de, B.G.E.} } @article {cite-key, title = {On a collection of fishes from the Congo; with description of some new species.}, journal = {Tijdschrift der Nederlandsche Dierkundige Vereeniging}, volume = {v.2}, number = {Ser. 2}, year = {1891}, pages = {83-92, Pl. 6}, keywords = {Synodontis greshoffi}, url = {https://biodiversitylibrary.org/page/9773023}, author = {Schilthuis, L.} } @article {225, title = {New fishes from the Gaboon and Gold Coast}, journal = {Annals and Magazine of Natural History (Series 3)}, volume = {20}, number = {116}, year = {1867}, month = {08/1867}, pages = {110{\textendash}117; Pls 2, 3.}, author = {G{\"u}nther, Albert C. L. G.} } @inbook {121, title = {Catalogue of the Fresh-Water Fishes of Africa in the British Museum (Natural History)}, booktitle = {Catalogue of the Fresh-Water Fishes of Africa in the British Museum (Natural History)}, volume = {I}, year = {1909}, pages = {29-145}, publisher = {British Museum (Natural History)}, organization = {British Museum (Natural History)}, address = {London}, url = {https://biodiversitylibrary.org/page/37889609}, author = {George A. Boulenger} } @book {902, title = {The fishes of the Nile}, series = {Zoology of Egypt}, year = {1907}, publisher = {Pub. for the Egyptian government by H. Rees, ltd.}, organization = {Pub. for the Egyptian government by H. Rees, ltd.}, address = {London}, doi = {10.5962/bhl.title.51710}, url = {http://www.biodiversitylibrary.org/item/110263$\#$page/1/mode/1up}, author = {George A. Boulenger} } @article {608, title = {A revision of the genera and species of fishes of the family Mormyridae}, journal = {Proceedings of the General Meetings for Scientific Business of the Zoological Society of London}, volume = {1898}, number = {Part 4}, year = {1899}, pages = {775-821}, url = {http://www.biodiversitylibrary.org/item/97095$\#$page/919/mode/1up}, author = {George A. Boulenger} } @article {622, title = {Pesci raccolti dal March. Saverio Patrizi nel bacino del Congo}, journal = {Annali del Museo Civico di Storia Naturale {\textquoteleft}Giacomo Doria{\textquoteright}}, volume = {53}, year = {1928}, month = {08/1928}, pages = {1{\textendash}28}, author = {Vinciguerra, D.} } @article {260, title = {Contribution {\`a} la faune ichthyologique du Congo Belge: Collections du Dr. H. Schouteden (1924-1926) et d{\textquoteright}autres r{\'e}colteurs}, journal = {Annales du Mus{\'e}e du Congo Belge (S{\'e}rie 1)}, volume = {3 (fasc. 5)}, year = {1937}, month = {05/1937}, pages = {189{\textendash}294}, author = {David, L. and Poll, M.} } @article {681, title = {Les poissons des Haut-Bassins de la Volta}, journal = {Annales du Musee Royal de l{\textquoteright}Afrique Centrale, S{\'e}rie 8, Sciences Zoologiques}, volume = {150}, year = {1966}, pages = {1{\textendash}191, Pls 1-7}, author = {Roman, B.} } @article {832, title = {Les poissons du bassin du Tchad et du bassin adjacent du Mayo Kebbi {\'e}tude syst{\'e}matique et biologique}, year = {1964}, pages = {1{\textendash}483}, publisher = {ORSTOM}, address = {Paris}, url = {http://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_2/memoires/19994.pdf}, author = {Blache, J.} } @article {144, title = {Les Poissons du Stanley-Pool}, journal = {Annales du Mus{\'e}e du Congo belge. C.{\textendash}Zoologie S{\'e}rie I.}, volume = {4}, number = {1}, year = {1939}, month = {12/1939}, pages = {1-60}, chapter = {1}, author = {Poll, M.} } @article {214, title = {An ecological and systematics survey of fishes in the rapids of the Lower Za{\"\i}re or Congo River}, journal = {Bulletin of the Museum of Comparative Zoology}, volume = {147}, number = {6}, year = {1976}, month = {02/1976}, pages = {239{\textendash}317}, url = {http://biodiversitylibrary.org/page/4276443}, author = {Roberts, T.R. and Stewart, D.J.} } @book {213, title = {Contribution {\`a} la Faune Ichthyologique de l{\textquoteright}Angola}, series = {Publica{\c c}{\~o}es Culturais}, number = {75}, year = {1967}, pages = {381}, publisher = {Companhia de Diamantes de Angola (DIAMANG)}, organization = {Companhia de Diamantes de Angola (DIAMANG)}, address = {Lisbon}, keywords = {Angola}, author = {Poll, M.} } @article {510, title = {Contribution a l{\textquoteright}{\'e}tude de la faune ichthyologique du bassin du fleuve S{\'e}n{\'e}gal. III. Mormyridae}, journal = {Bulletin de l{\textquoteright}Institut Fran{\c c}ais d{\textquoteright}Afrique Noire}, volume = {35}, year = {1973}, pages = {665-704}, chapter = {665}, author = {Reizer, C. and Mattei, X. and Chevalier, J.L.} } @article {155, title = {Le genre Mormyrops (Pisces, Mormyridae) en Afrique de l{\textquoteright}Ouest}, journal = {Revue d{\textquoteright}Hydrobiologie Tropicale}, volume = {20}, year = {1987}, pages = {145-164}, chapter = {145}, author = {Bigorne, R.} } @article {831, title = {Aspects of the reproductive biology of Hippopotamyrus pictus from Lake Kainji, with notes on four other mormyrid species}, journal = {Journal of Fish Biology}, volume = {11}, number = {5}, year = {1977}, pages = {437{\textendash}445}, abstract = {

A method is descrihed for the assessment of fecundity in in mormyrrd fish. In all species examined a tri-modal egg size distribution was found in the mature pre-spawning ovary. These modes represented one oocyte and two ova components. The significance of the presence of two sizes of ovum is discussed in relation to breeding periodicity in Hippopotamyrus pictus. Size and age at first maturity are estimated for this species. The probable effects of the formation of the lake on the breeding behaviour of mormyrids is discussed.

}, url = {http://onlinelibrary.wiley.com/store/10.1111/j.1095-8649.1977.tb04138.x/asset/j.1095-8649.1977.tb04138.x.pdf?v=1\&t=hqzjgrlk\&s=80a89cbded91f381ca05b0ee20d62e74d4487e99}, author = {Blake, B.F.} } @book {159, title = {The Mormyridae and other Osteoglossomorpha (CD-ROM)}, series = {World Biodiversity Database, CD-ROM Series}, volume = {2000}, year = {2000}, publisher = {Springer Verlag, ETI-UNESCO}, organization = {Springer Verlag, ETI-UNESCO}, address = {New York}, issn = {Hyb: 3-540-14811-6}, url = {https://www.amazon.com/Mormyridae-Osteoglossomorpha-Biodiversity-Database-CD-ROM/dp/3540148116}, author = {Harder, W.} } @inbook {158, title = {Mormyridae}, booktitle = {Faune des poissons d{\textquoteright}eaux douces et saum{\^a}tres de l{\textquoteright}Afrique de l{\textquoteright}Ouest}, volume = {1}, year = {2003}, pages = {154-222}, publisher = {IRD/MNHN/MRAC}, organization = {IRD/MNHN/MRAC}, url = {http://www.ird.fr/editions/catalogue/ouvrage.php?livre=409}, author = {Bigorne, R.} } @inbook {179, title = {Mormyridae}, booktitle = {Faune des poissons d{\textquoteright}eaux douces et saum{\^a}tres de l{\textquoteright}Afrique de l{\textquoteright}Ouest = The fresh and brackish water fishes of West Africa}, series = {Faune tropicale 28}, year = {1990}, pages = {122-184}, publisher = {ORSTOM, MRAC}, organization = {ORSTOM, MRAC}, address = {Paris, Tervuren (Belgium)}, url = {http://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_6/Fau_trop/34060.pdf}, author = {Bigorne, R.}, editor = {L{\'e}v{\^e}que, C. and Paugy, D. and Teugels, G.G.} } @inbook {152, title = {12. Mormyridae}, booktitle = {The Fresh and Brackish Water Fishes of Lower Guinea, West-Central Africa}, series = {Collection Faune et Flore Tropicales 42}, volume = {1}, year = {2007}, pages = {220{\textendash}334}, publisher = {IRD}, organization = {IRD}, chapter = {12}, isbn = {978-2-7099-1621-9}, author = {Carl D Hopkins and S{\'e}bastien Lavou{\'e} and John P Sullivan}, editor = {Melanie L.J. Stiassny and Teugels, G.G. and Carl D Hopkins} } @article {852, title = {Morphological and electrophysiological field observations on electric freshwater fish of the genus Mormyrops M{\"u}ller 1843 (Teleostei: Mormyridae) from West and southern Africa}, journal = {African Journal of Aquatic Science}, volume = {38}, year = {2013}, month = {11/2013}, pages = {31 - 41}, abstract = {

Different specimens of Mormyrops anguilloides (Linnaeus 1758) were reported to display electric organ discharge (EOD) pulses of either initially head-positive or initially negative polarity, a hypothetical sex difference that has not been substantiated to date. The morphology and EODs of M. anguilloides of both sexes and a sexually mature size from the Comoé and Bandama rivers, Côte d\’Ivoire, and the Lower and Middle Zambezi, Mozambique, displayed initially positive EODs. The morphologically similar M. breviceps Steindachner 1895 of both sexes and a sexually mature size from the Bandama River displayed initially head-negative EODs of biphasic waveform and long duration (0.93\–1.15 ms) in the very-low-frequency spectral range. Mormyrops anguilloides from the Comoé and Bandama rivers were differentiated in caudal peduncle depth and in EOD waveform, pulse duration and spectral energy content. The former samples displayed a biphasic, lower-frequency EOD pulse of up to 0.42 ms duration, the latter a tetraphasic, high-frequency EOD of up to 0.33 ms. It is suggested that reports of EODs of both polarities in M. anguilloides indicate the presence of an unrecognised species.

}, issn = {1727-9364}, doi = {10.2989/16085914.2013.791244}, url = {http://dx.doi.org/10.2989/16085914.2013.791244}, author = {Bernd Kramer} }