Taxonomy & naming
Stomatorhinus patrizii was described by the Italian ichthyologist Decio Vinciguerra in 1928. It belongs to the family Mormyridae, the elephantnoses and mormyrids, within Osteoglossiformes, the ancient lineage of bonytongue fishes. The genus Stomatorhinus groups a number of small mormyrids from the Congo basin, distinguished from most of their relatives by a small mouth set on the underside of the snout rather than at its tip. Stomatorhinus patrizii is treated as a valid name in Eschmeyer's Catalog of Fishes, the standard reference for fish nomenclature, but the species has drawn little attention beyond its original description — it is one of many small Congo-basin mormyrids known mainly from museum material and basin-wide surveys rather than from any dedicated study.
The genus name Stomatorhinus combines the Greek stoma (mouth) and rhis, rhinos (nose, snout) — 'mouth-snout' — a reference to the small ventral mouth set back from the point of the snout that distinguishes the genus from closer-mouthed relatives such as Marcusenius. The species epithet patrizii carries the Latin patronymic ending -ii, marking it as a dedication to a person named Patrizi, very likely a collector connected to the material Vinciguerra worked from. The identity of that person and the reasoning behind the dedication are not stated in the sources available for this account.
Morphology
Like other members of its genus, Stomatorhinus patrizii is a small fish — Stomatorhinus species are mostly under 4 in in length — though no specific maximum length has been published for this species in the sources available for this account. The body follows the general mormyrid plan: laterally compressed, with a short, blunt head and a small mouth set beneath the snout rather than at its tip, an arrangement suited to picking food items off the surface of mud, sand or leaf litter rather than digging into the substrate.
As in every mormyrid, an electric organ near the base of the tail generates a weak, continuous pulse discharge, read back through electroreceptors spread across the skin. This electric sense lets the fish orient and detect prey and other fish in dark, silt-laden water where eyesight is of limited use. No electric organ discharge waveform has been published specifically for Stomatorhinus patrizii, so nothing can be said here about how its signal compares with those of related species.
Habitat
Stomatorhinus, as a genus, is centered on the Congo River basin in Central Africa, where its species occupy forest streams and swamp habitats away from the main river channels. No locality record specific to Stomatorhinus patrizii beyond the original description is available in the sources consulted for this account, and no water chemistry data — temperature, pH or hardness — has been published for it. Congo basin forest-stream habitats of the kind favored by the genus are typically warm, shaded by canopy, carrying heavy leaf litter, and often soft and acidic, but that description should be read as context for the genus rather than a measured record for this species.
Feeding
No dietary study has been published for Stomatorhinus patrizii specifically. Mormyrids in general are benthic invertebrate feeders, using electrolocation to find insect larvae, worms and small crustaceans hidden in mud, sand and leaf litter, and there is no reason to expect this species to differ from that pattern, though it has not been confirmed by direct observation.
Mating
No courtship or spawning behavior has been recorded for Stomatorhinus patrizii. In mormyrids generally, the electric organ discharge is thought to carry information used in species and sex recognition and, in some studied genera, in courtship signaling, but this has not been investigated in Stomatorhinus patrizii itself, and extending that pattern to this species would be speculation rather than a documented finding.
Breeding
Breeding in Stomatorhinus patrizii is unrecorded. No wild spawning account or captive breeding has been published for this species, and mormyrid reproduction as a whole remains poorly studied outside a handful of better-known genera. Nothing can be said here about egg-laying sites, clutch size, or parental care in this species.
In the aquarium
Stomatorhinus patrizii is essentially absent from the aquarium hobby. It does not appear to have an established keeping history, and no aquarium account of the species has been found for this profile. Small mormyrids as a group are kept successfully only with particular care — soft sand for probing, dim lighting, ample cover, live or frozen invertebrate foods rather than flake, and gradual acclimation, since the family is unusually sensitive to poor water quality and to some common medications.
None of this amounts to a documented account of keeping this particular species. It describes what caring for a small Stomatorhinus would likely require, drawn from general mormyrid husbandry, rather than a track record this species actually has.
Conservation
Stomatorhinus patrizii has not been evaluated by the IUCN Red List. No species-specific assessment, population trend, or threat list is available for it. As with other small mormyrids restricted to Congo basin forest streams, general pressures on that basin — deforestation, siltation and habitat conversion — are the kind of long-term concerns that could affect it, but without a formal assessment this remains a general expectation rather than a documented finding.