Taxonomy & naming
Petrocephalus bovei was described by Achille Valenciennes in 1847, from a specimen supplied to the Muséum National d'Histoire Naturelle in Paris. The parenthetical authority — (Valenciennes, 1847) — signals that the species was originally placed in a different genus before later work moved it into Petrocephalus; this kind of reshuffling is common across the mormyrids, a family whose internal genera were worked out gradually through the nineteenth and twentieth centuries. The Catalog of Fishes treats Petrocephalus bovei as the valid name, and both FishBase and GBIF list Mormyridae as its family within the order Osteoglossiformes.
Osteoglossiformes is one of the oldest living lineages of teleost fish, named for a bony, toothed structure on the tongue that bites against toothed plates on the roof of the mouth in many of its members. The order split early into a scattered, deep-time radiation found today on four continents — the arowanas and arapaima of South America, the featherback knifefishes and elephantnoses of Africa, and further relatives in Southeast Asia and Australasia. Mormyridae, the family that holds Petrocephalus, is an entirely African branch, and its defining trait is not the tongue bone but a weak electric sense that the group evolved independently of any other fish lineage.
The genus name Petrocephalus comes from the Greek petros, "stone", and kephale, "head", a reference to the thick, bony skull typical of the genus. The species epithet bovei honors Nicolas Bové (1812–1841), a Luxembourg-born gardener and botanist who collected the type specimen and supplied it to the Paris museum.
Morphology
Petrocephalus bovei is a small, deep-bodied mormyrid, reaching roughly 4.5 in in length. The body is laterally compressed, with a short, blunt snout and a small, low-set mouth — unlike the elongated, trunk-like chin appendage (the schnauzenorgan) of the better-known elephantnose, Gnathonemus petersii, with which it is sometimes confused in the trade. Colouration is a uniform, bright silver, occasionally shading toward grey or brown, with no strong pattern or barring.
As in all mormyrids, an electric organ sits in the caudal peduncle near the tail, generating a weak, pulse-type electric field. The fish reads distortions in that field through electroreceptors spread over its skin, an ability called electrolocation, and uses the same discharge to signal other fish. Mormyrids carry an unusually large cerebellum relative to body size — among the highest brain-to-body ratios recorded in fish — reflecting the processing load of running a real-time electrosensory system, not a general claim about intelligence.
Habitat
Petrocephalus bovei is widespread across West African freshwater systems, recorded from the Senegal, Gambia and Volta River basins, the Lake Chad basin, the Niger system and the upper Nile, with additional records from Côte d'Ivoire. It is a tropical, freshwater, bottom-dwelling (demersal) fish.
The species is potamodromous, meaning it makes migrations entirely within fresh water rather than to the sea, movements that in West African river systems are typically tied to seasonal flooding. Water temperature across its range runs about 73–79 °F. Like other mormyrids it favours slow-flowing water that is often turbid or dimly lit, the conditions its electric sense is built to work in rather than a fish that relies on eyesight.
Feeding
Petrocephalus bovei feeds mainly on small benthic invertebrates — insect larvae, worms and other tiny animals picked out of sediment and cover on the riverbed. It locates prey largely by electrolocation rather than sight, an advantage in the turbid or low-light water it inhabits.
It is a night feeder, most active after dark, and in the aquarium should be fed once the lights are off or the tank is dim; otherwise it is easily out-competed by more visually oriented tankmates. Small sinking foods — bloodworm and other soft frozen invertebrate foods — suit it well, and it does not need live food.
Mating
Little is published on courtship in Petrocephalus bovei specifically. Research on the species has linked variation in its electric organ discharge to aggregative behaviour — fish showing certain discharge patterns tend to associate more closely with others — which points to the EOD carrying social as well as electrolocation information, as it does across the mormyrid family generally. Beyond that association, how discharge signals translate into pairing or spawning has not been worked out for this species.
As in most mormyrids, breeding is presumed to follow seasonal cues tied to the flood pulse of its home rivers rather than a fixed cycle, but direct field observations of spawning behaviour in Petrocephalus bovei are sparse.
Breeding
Petrocephalus bovei is a fractional spawner, releasing eggs in batches over an extended period rather than a single clutch, and is reported to build a nest. No parental care of eggs or fry has been documented — once the eggs are laid, the adults do not appear to guard or tend them.
The species is rarely if ever bred in the home aquarium. Aquarium sources describe captive spawning as essentially unreported, consistent with the wider pattern across Mormyridae, where flood-triggered wild spawning cues and electric-sense-driven courtship are difficult to replicate in a tank. Aquarium stock is generally wild-caught rather than captive-bred.
In the aquarium
Petrocephalus bovei is a manageable mormyrid for a fishkeeper who respects its needs. A tank of at least 25 US gal with a soft, sandy substrate, dim lighting and plenty of cover — driftwood, roots, dense planting — suits it well; it is a night feeder that appreciates shade during the day. It does best kept in a group of six or more, which also matches its naturally aggregative tendencies.
It is distinct from the more familiar Peters's elephantnose (Gnathonemus petersii), which has the long, mobile chin barbel and is usually kept singly; Petrocephalus bovei lacks that appendage and is more social. It should not, however, be housed with other Mormyridae — interspecific aggression between electric fish species is a recognised problem in the family. As in most mormyrids, breeding in the aquarium should not be expected.
General mormyrid husbandry cautions apply here too: the group is known to be sensitive to poor water quality and to some medications, so it should go into a fully cycled tank and be monitored closely after any water change or treatment.
Conservation
The IUCN Red List assesses Petrocephalus bovei as Least Concern, an assessment made in 2019. The species is not considered threatened, reflecting its wide distribution across multiple West African river basins from the Senegal system to the Nile.
As with many wide-ranging Sahelian and West African river fish, no population-specific threats are documented for this species; the main long-term pressures on its river systems generally are damming, water abstraction and habitat degradation, though none is flagged as a specific concern for Petrocephalus bovei in the assessed literature.