Taxonomy & naming
Pollimyrus brevis was described by the ichthyologist George Albert Boulenger in 1913. It belongs to the family Mormyridae — the elephantnoses and mormyrids — within the order Osteoglossiformes, the bonytongue fishes, one of the oldest surviving lineages of teleosts. Boulenger described a large share of the mormyrid species known from West and Central Africa in the early twentieth century, mostly from museum collections rather than fieldwork of his own.
The genus Pollimyrus was not established until 1971, when the ichthyologist Jacques Taverne split a group of smaller-bodied mormyrids away from the broader genus Marcusenius. Boulenger's original generic placement, this species' type locality, and any subsequent synonymy are not confirmed in the sources reviewed for this account, and this article does not speculate about them.
Morphology
Specific measurements for Pollimyrus brevis were not found in the sources reviewed for this account. Species in the genus Pollimyrus are, without exception, small mormyrids — most mature well under 6 in — but no maximum-length figure specific to this species could be confirmed here, and none is substituted in its place.
As in every mormyrid, an electric organ near the base of the tail generates a weak, pulse-type electric field that Pollimyrus brevis reads through electroreceptors spread across its skin — the sense that compensates for the family's generally poor eyesight in murky or nighttime water. Mormyrids also carry one of the highest brain-to-body mass ratios of any vertebrate group, with an enlarged cerebellum devoted to processing this electrosensory stream. No electric organ discharge waveform specific to Pollimyrus brevis has been published in the sources reviewed here.
Habitat
No confirmed locality records for Pollimyrus brevis were found in the sources reviewed for this account. The genus Pollimyrus as a whole is distributed across tropical Africa, from West African coastal rivers through the Congo basin to the Nile and parts of southern Africa, but nothing in the available sources ties this particular species to a specific country, river system, or drainage, and none is assigned here.
Water chemistry and temperature data are likewise undocumented for this species. Mormyrids in general favour slow, turbid, structure-rich water — backwaters, flooded margins, and quiet river reaches with cover from roots or vegetation — where an electric sense outperforms eyesight, but that is a family-level generalisation rather than a measurement taken for Pollimyrus brevis.
Feeding
No diet study specific to Pollimyrus brevis was found in the sources reviewed for this account. Mormyrids as a group are bottom-foraging invertebrate feeders, using electrolocation to find insect larvae, worms, and small crustaceans hidden in mud, silt, and leaf litter before taking them with a quick strike of the mouth. This species is presumed to feed the same way, though that has not been confirmed specifically for it.
Mating
Courtship and mating behaviour have not been described for Pollimyrus brevis. In mormyrids generally, the electric organ discharge is more than a navigation tool: its pulse pattern is species- and often sex-specific, and it is thought to play a part in recognising potential mates and in shoal cohesion. Whether that applies to Pollimyrus brevis specifically is unknown — no courtship study of this species has been located, and the acoustic courtship signalling documented in the well-studied congener Pollimyrus isidori has not been shown to occur in this species and is not assumed here.
Breeding
Breeding has not been recorded for Pollimyrus brevis, in the wild or in captivity, in any source reviewed for this account. Spawning behaviour, egg or larval description, and parental care are all unknown for this species. As with most small African mormyrids, any account of its reproduction would currently be speculation, and none is offered here.
In the aquarium
Pollimyrus brevis has essentially no documented presence in the aquarium hobby; no keeping reports, husbandry notes, or import records specific to this species were found in the sources reviewed here. What follows describes general practice for small mormyrids rather than any track record established for this particular fish.
Mormyrids as a group need a soft substrate for probing, ample cover, dim lighting, and stable water with low turbidity; the family is also known for unusual sensitivity to some medications and to poor water quality, which argues for gradual acclimation and conservative dosing whenever a mormyrid is treated for disease. They typically refuse dry foods and need live or frozen invertebrate foods such as bloodworm and brine shrimp, offered after the lights dim to match their nocturnal foraging habit. None of this has been verified specifically for Pollimyrus brevis, but it reflects standard practice across the family it belongs to.
Conservation
Pollimyrus brevis does not appear to carry a current IUCN Red List assessment, based on the sources reviewed for this account. No population trend, range size, or specific threat has been documented for this species.
Many small, narrowly distributed African mormyrids have never been formally assessed, and the general pressures facing African freshwater systems — habitat degradation, siltation, and water-quality decline — are the kind of long-term risk that could affect any of them. No such threat has been documented specifically for Pollimyrus brevis, and none is asserted here.