Brienomyrus brachyistius (Gill, 1862)
photo by JJPhoto

Family:  Mormyridae (Elephantfishes)
Max. size:  20 cm TL (male/unsexed)
Environment:  benthopelagic; freshwater; brackish
Distribution:  Africa: Gambia to Democratic Republic of the Congo. May also be present in the upper reaches of Senegal (Niokolo-Koba National Park) (Ref. 2915).
Diagnosis:  Dorsal spines (total): 0-0; Dorsal soft rays (total): 14-19; Anal spines: 0-0; Anal soft rays: 25-31. Dorsal base 0.41-0.68 x anal fin base. Pectorals as long as head, posterior end does not extend origin of pelvic fins. Caudal peduncle thin, height 14.4-22.9x of SL. Dark grey-black or brown coloration.
Biology:  Affinities: Brienomyrus longianalis. Occurs in most coastal basins in West Africa (Ref. 2703). Within this species complex, four distinct waveforms of electric organ discharge (EOD) were noted in the Gabon (Ivindo River) populations, probably pointing to separate species (Ref. 10460). Exhibits sexual dimorphism in its EOD waveform and duration (Ref. 10011; 10764 ). EOD has a constant waveform and variable sequence of pulse intervals (SPI) (Ref. 55567).
IUCN Red List Status: Least Concern (LC); Date assessed: 23 October 2019 Ref. (130435)
Threat to humans:  harmless

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