Taxonomy & naming
Chiloglanis benuensis was described by the French ichthyologists Jacques Daget and Jacques Stauch in 1963, with a type locality on the Bénoué (Benue) River at Lakdo, Cameroon — the river that gives the species its epithet. It belongs to the family Mochokidae, the African squeakers and upside-down catfishes, in the suckermouth genus Chiloglanis, a group of small rheophilic (current-loving) catfishes found across sub-Saharan Africa. The Catalog of Fishes (Eschmeyer, CAS) treats Chiloglanis benuensis as the valid name.
Chiloglanis is a large genus of similarly built, hard-to-tell-apart small suckermouth squeakers, and species limits within it have been revised repeatedly as more populations are sampled; benuensis is one of several described from the Niger–Benue and Chad drainages. As with its relatives, field identification leans on the mouth disc, barbel count and fin details rather than colour pattern, which is fairly plain across the genus.
Morphology
This is a genuinely small catfish: the recorded maximum is about 1.5 in standard length, among the smallest members of an already diminutive genus. The head is broad and flattened, carrying a distinctive ventral suckermouth — a disc-like, sucker-modified lower lip used to cling to rock in fast water — fringed with barbels, with up to three auxiliary mandibular barbels reported in the species. The adipose fin is notably long, running well back along the body, a useful field mark within Chiloglanis.
Like all mochokids the skin is naked and scaleless, which matters directly for medication dosing (see "In the aquarium"). Body colour is a muted brown-to-olive mottle that blends into rock and gravel substrate, consistent with a fish that spends its life pressed against current-swept stone rather than swimming in open water.
Habitat
Chiloglanis benuensis is native to the Benue River — the major right-bank tributary of the middle Niger — in Nigeria and Cameroon, with records extending into the Chad basin. It occupies fast-flowing, well-oxygenated stretches of river over rock, gravel and cobble, the classic rheophilic niche exploited across the genus: the suckermouth lets it hold station directly in current that would sweep a normal-bodied fish downstream.
As a small West/Central African riverine species it is a warm-water fish; the cache does not carry a precise measured pH/hardness range for this population specifically, so exact figures are left unstated here rather than guessed — but the habitat is flowing, oxygen-rich river water, not the still, soft, tannin-stained blackwater sometimes assumed for African species. Aquarists should replicate current and oxygenation more than any particular hardness.
Feeding
Chiloglanis benuensis is a nocturnal benthic forager, grazing the algal and microbial biofilm ('aufwuchs') coating rocks and gravel and picking off small invertebrates, much like the wider rock-clinging Chiloglanis group. Its suckermouth is built for adhering to substrate while it grazes rather than for grabbing large prey.
In the aquarium it should be offered sinking foods that reach the bottom after dark — algae wafers, blanched vegetables, and small sinking pellets or frozen foods — rather than food that is only taken at the surface. Because it forages mostly at night, feeding after lights-out helps ensure it is not out-competed by more active daytime tankmates.
Mating
Specific courtship and spawning behaviour for Chiloglanis benuensis is not documented in the sources available here. FishBase records the species as oviparous with distinct pairing at breeding, indicating paired rather than group spawning, consistent with reports for other small rheophilic Chiloglanis, but the fine detail of how pairs select mates or where eggs are laid in this species has not been described in the literature consulted.
Breeding
Chiloglanis benuensis is not known to be bred in the home aquarium; it is not a commercially propagated species and the aquarium trade, where it appears at all, relies on wild-collected fish. Given its lifestyle as a current-dependent rock-clincher, any spawning likely follows the wider Chiloglanis pattern of eggs laid in crevices or under stones in flowing water rather than open-water scattering or a bubble-nest, but this has not been confirmed for the species specifically — it should not be assumed achievable in a standard tank. No parental-care behaviour is documented.
In the aquarium
This is one of the rare catfish where the size trap runs the other way: at a maximum of roughly 1.5 in, Chiloglanis benuensis stays genuinely tiny and never demands the room-sized tank that so many larger catfish eventually need. That does not make it easy — it is a specialised rheophilic species that needs strong water movement and high dissolved oxygen (a powerhead or river-manifold setup) plus a rock- and gravel-based substrate it can graze and cling to; it is a poor fit for a still-water community tank.
As with all mochokids its skin is naked and scaleless, so it is more sensitive than scaled fish to copper and to some medications — dose conservatively. It also carries the family's stiff, locking pectoral spines, small as they are on a fish this size, so handle and net it gently. Being nocturnal, it appreciates rock and gravel cover to retreat into by day and is best fed after dark. Given how little is documented about its aquarium husbandry, it suits an experienced keeper willing to replicate fast-flowing, well-oxygenated river conditions rather than a beginner community setup.
Conservation
The IUCN Red List assesses Chiloglanis benuensis as Least Concern. It is known from the Benue River system (middle Niger basin) in Nigeria and Cameroon and from the Chad basin, a reasonably broad riverine range for a small, specialised species, which supports the non-threatened assessment.
As with other small riverine fishes in the Niger–Benue and Chad systems, longer-term pressures worth watching are the general ones facing West and Central African rivers — damming, siltation and water-quality decline from agriculture and development — even though no specific elevated threat is recorded for this species at present.