Taxonomy & naming
Pollimyrus maculipinnis was described by the American ichthyologists John T. Nichols and Francesca La Monte in 1934. It belongs to the genus Pollimyrus, a group of small mormyrids sometimes called dwarf stonebashers, within the family Mormyridae — the elephantnoses and mormyrids — in the order Osteoglossiformes, the ancient bonytongue lineage of teleost fishes. The original type locality, and any subsequent taxonomic revision or synonymy specific to this species, are not documented in the sources available for this account and should not be assumed from other, better-studied members of the genus.
The genus name Pollimyrus honors the Belgian ichthyologist Max Poll, who spent much of his career revising the mormyrid fishes of the Congo basin, combined with -myrus, a suffix drawn from Mormyrus (itself from the ancient Greek mormyros, a name originally applied to an unrelated marine fish) and repeated across the family's genus names — Hippopotamyrus, Brienomyrus and Myomyrus among them. The species epithet maculipinnis is built from the Latin macula (spot) and pinna (fin), meaning 'spotted-finned' — presumably a reference to markings on the fins used to separate it from similar congeners, though the original description's exact reasoning is not confirmed here.
Morphology
Species-specific measurements for Pollimyrus maculipinnis are not documented in the sources available for this account. Like the rest of its genus, it is presumably a small fish rather than one of the larger, trunk-snouted mormyrids sold as 'elephantnose' — Pollimyrus species generally have a laterally compressed body, a short, blunt head, and a small mouth set toward the underside of the snout, distinct from the long chin barbel (the schnauzenorgan) that marks the related genus Gnathonemus.
As in every mormyrid, an electric organ near the base of the tail generates a weak, pulse-type discharge, picked up by electroreceptors spread across the skin. The fish uses this sense, electrolocation, to navigate and find food in murky or nighttime water where eyesight is of limited use. No species-specific electric organ discharge waveform has been published for Pollimyrus maculipinnis, and visual identification within Pollimyrus is generally unreliable — the discharge itself is often the more dependable marker between similar species.
Habitat
Pollimyrus maculipinnis is native to tropical Africa, in keeping with the rest of the family Mormyridae, but the specific river system, country records, and habitat description for this species are not documented in the sources available for this account. Species in the genus Pollimyrus are distributed across the continent, from West African coastal rivers to the Congo and Zambezi drainages further east, and each is typically confined to a single river system rather than ranging continent-wide.
Mormyrids in general favor slow, often turbid water with cover — muddy backwaters, vegetated margins, and quiet river reaches — where an electric sense outperforms eyesight. Whether that description applies to Pollimyrus maculipinnis specifically is a reasonable expectation for the genus, not a documented fact for this species, and it is presented here as such.
Feeding
No species-specific feeding study has been published for Pollimyrus maculipinnis, but the family's foraging strategy is well documented and safe to generalize here. Mormyrids use electrolocation to find small invertebrates — insect larvae, worms, and tiny crustaceans — hidden in mud, silt, or leaf litter, then take them with a quick strike of the small mouth. There is no confirmed account of this species being fed in captivity.
Mating
No courtship or mating behavior has been documented for Pollimyrus maculipinnis. In the related species Pollimyrus isidori, males are known to produce sounds during courtship alongside their electric organ discharge, a combined acoustic-and-electric signaling system that has made P. isidori a laboratory model for studying fish communication. That finding is specific to P. isidori and the handful of relatives studied alongside it in the laboratory, and it should not be extended to Pollimyrus maculipinnis without direct evidence, which does not currently exist.
Breeding
Breeding has not been recorded for Pollimyrus maculipinnis, in the wild or in the aquarium. As with the great majority of the roughly two dozen species in Pollimyrus, this is a fish with essentially no reproductive record in the literature available for this account, and any description of its spawning behavior should be treated as unsupported unless a specific source is cited.
In the aquarium
Pollimyrus maculipinnis has essentially no track record in the aquarium hobby. It does not appear to be part of the regular ornamental trade, and no husbandry account specific to this species could be confirmed for this profile — what follows is general practice for keeping a small mormyrid, not a documented history for this fish. Mormyrids as a group do best over a soft substrate they can probe with their electric sense, with dim lighting and plenty of cover, since bright, open tanks tend to stress them; live and frozen invertebrate foods such as bloodworm and brine shrimp are usually needed, since mormyrids rarely take dried food.
Mormyrids are also known to be sensitive to poor water quality and to some common aquarium medications, so gradual acclimation and conservative dosing are standard advice across the family, and there is no reason to expect this species to be an exception. A fish sold under this name should be treated as a long-term commitment to a poorly known, almost certainly wild-caught species rather than an easy beginner mormyrid.
Conservation
No IUCN Red List assessment for Pollimyrus maculipinnis could be confirmed for this account. Whether that reflects a genuine Not Evaluated status or simply a gap in the sources consulted here is not established, so its conservation status should be treated as unknown rather than assumed safe.
No species-specific threats have been documented. In general terms, small-range African mormyrids confined to a single river system face the same long-term pressures as other freshwater fish on the continent — habitat degradation, siltation, and water-quality decline — but extending that general concern to this species specifically would go beyond what is currently documented.