Taxonomy & naming
Albert Günther named Pollimyrus adspersus in 1866, one of a large number of West and Central African mormyrids he described that decade while working through fish material held at the British Museum. The species sits in the family Mormyridae, the elephantnoses and mormyrids, within the order Osteoglossiformes — the bonytongue fishes, among the most ancient lineages of living teleosts.
The genus Pollimyrus did not exist when Günther wrote his description; it was carved out in 1971 by the Belgian ichthyologist Léon Taverne, who separated a cluster of smaller-bodied mormyrids from the much larger genus Marcusenius on the strength of osteological differences. What genus Günther originally placed this species in, where the type specimen was collected, and whether any name has since been synonymized with it are not stated in the sources reviewed for this account, so none of that is asserted here.
Morphology
No maximum-length figure specific to Pollimyrus adspersus was found in the sources reviewed for this account. Every species placed in Pollimyrus is a small-bodied mormyrid, and most mature at well under 6 in, but that is a statement about the genus as a whole rather than a measurement taken from this species, and nothing here should be read as filling that gap.
As in all mormyrids, a weak electric organ near the base of the tail produces a pulse-type discharge that the fish detects through electroreceptors spread across its skin, a sense that stands in for eyesight in dark or turbid water. Mormyrids as a group also carry an unusually large brain relative to body size, with an oversized cerebellum given over to processing this electrosensory input. No discharge waveform or other morphological detail specific to Pollimyrus adspersus has been published in the sources consulted here.
Habitat
No confirmed locality record for Pollimyrus adspersus turned up in the sources reviewed for this account, and none is stated here. The genus Pollimyrus as a whole is spread across tropical Africa, from coastal West African rivers through the Congo basin to parts of the Nile system and southern Africa, but that range describes the genus, not a documented distribution for this particular species.
Temperature, pH, and other water-chemistry figures are likewise undocumented for Pollimyrus adspersus. Mormyrids in general are found in slow-moving, turbid water with plenty of structure — flooded margins, backwaters, and river stretches thick with roots or submerged vegetation — settings where an electric sense works better than eyes. That is a pattern true of the family broadly, not a habitat description confirmed for this species.
Feeding
No diet study specific to Pollimyrus adspersus is available in the sources reviewed for this account. Mormyrids as a family forage along the bottom for small invertebrates — insect larvae, worms, tiny crustaceans — locating them by electrolocation in mud, silt, and leaf litter before snapping them up with a quick strike of the mouth. This species almost certainly feeds the same way, but that has not been confirmed for it specifically, and it is presented here as an inference rather than an established fact.
Mating
Nothing has been published on courtship or mate choice in Pollimyrus adspersus. Across mormyrids generally, the electric organ discharge does more than help the fish navigate: its pulse pattern varies by species and often by sex, and researchers think it plays a role in recognizing potential mates and holding shoals together. A well-studied congener, Pollimyrus isidori, is even known to pair electric signaling with audible grunts during courtship — but that finding belongs to isidori alone, has not been shown in Pollimyrus adspersus, and is not assumed to apply here.
Breeding
Breeding in Pollimyrus adspersus has not been recorded, in the wild or in an aquarium, in any source reviewed for this account. Nothing is known about its spawning behavior, its eggs or larvae, or whether either parent provides care. As with most small African mormyrids, any specific claim about how this species reproduces would be invention rather than fact, so none is offered.
In the aquarium
Pollimyrus adspersus has essentially no track record in the aquarium hobby — no keeping reports, husbandry write-ups, or import records specific to this species turned up in the sources reviewed here. What follows is general mormyrid practice, not anything demonstrated for this particular fish.
Small mormyrids generally do best over a soft, fine substrate they can probe with the snout, with heavy cover and subdued lighting suited to a fish that is more active after dark. The family is also known for being unusually sensitive to poor water quality and to a number of common aquarium medications, so cautious, gradual dosing matters more here than with most fish. Live or frozen invertebrate foods such as bloodworm and brine shrimp are the standard diet, since mormyrids typically ignore dry foods outright. None of this has been verified for Pollimyrus adspersus specifically, but it reflects how the rest of its family is kept.
Conservation
No current IUCN Red List assessment for Pollimyrus adspersus was located in the sources reviewed for this account. No population trend, range extent, or specific threat has been published for this species.
A great many small, narrow-range African mormyrids have simply never been formally assessed, and this species may fall into that category rather than genuinely lacking any conservation concern. Broad pressures on African freshwater systems — habitat degradation, siltation, and declining water quality — are long-term risks facing the group as a whole, but none has been documented specifically for Pollimyrus adspersus, and none is claimed here.