Taxonomy & naming
Chiloglanis dialloi was described by Schmidt & Pezold in 2017 from the Moa River system of Guinea. It belongs to the family Mochokidae, the African squeakers and upside-down catfishes, and to the genus Chiloglanis, a large group of small suckermouth squeakers distributed across sub-Saharan Africa's fast-flowing rivers. The Catalog of Fishes treats Chiloglanis dialloi as the currently valid name; being a comparatively recent (2017) description, it has not been shuffled through older genus combinations the way many nineteenth-century catfish names have.
The genus name Chiloglanis is built from Greek roots referring to the lip-derived sucker mouth that defines the group. The species epithet dialloi honours Samba Diallo, who assisted the describers' field expeditions to the Moa River system in the 2000s and 2010s. As with many small riffle-dwelling Chiloglanis, C. dialloi is best distinguished from its West African relatives by fine details of its sucker-disc structure and body proportions rather than by colour pattern alone.
Morphology
Like other members of its genus, Chiloglanis dialloi has a flattened head and a distinctive oral disc: the lips and barbels are modified into a fleshy, sucker-like structure on the underside of the head, allowing the fish to adhere to rock surfaces in current the way a plecostomus uses its mouth, though the two groups are unrelated. The body is scaleless (naked-skinned), a trait shared across the Mochokidae, and it carries the family's typical stiff, serrated pectoral and dorsal spines that can be locked erect.
This is a genuinely small catfish: maximum recorded size is only about 2 in standard length. That modest ceiling is unusual among catfish, where the size trap — a juvenile sold small that grows into an unmanageable adult — is the single most common care failure; C. dialloi is one of the few Siluriformes where the cache-confirmed adult size stays truly diminutive throughout life.
Habitat
Chiloglanis dialloi is known only from the Moa River drainage in Guinea, with a possible extension into neighbouring Sierra Leone. This is a West African rainforest river system, and like other riffle Chiloglanis, the species lives on rocky and boulder-strewn substrates in fast-flowing, well-oxygenated stretches of river rather than in still water.
The cache does not report specific water-chemistry measurements for the Moa River population, so exact temperature and pH figures are not given here rather than guessed; what is well documented for the genus generally is a preference for flowing, oxygen-rich habitat over quiet pools, and that should guide any aquarium approximation of its native conditions.
Feeding
Chiloglanis species graze the biofilm and invertebrate life of rock surfaces in fast water, taking mayfly and caddisfly nymphs, blackfly and midge larvae, and small snails from the algae-and-detritus film coating boulders — a nocturnal benthic micro-predator and grazer rather than an open-water hunter. Foraging activity in the genus is concentrated after dark, when the fish are less exposed to daytime predators.
In an aquarium setting this diet translates to sinking foods offered after lights-out — pellets and frozen foods aimed at the bottom — supplemented by whatever biofilm develops on rockwork in a mature, well-established tank. Because it forages mostly at night, C. dialloi is easily out-competed by more active daytime tankmates if fed only during the day.
Mating
No courtship or spawning behaviour has been documented for Chiloglanis dialloi in the cache material, and detailed reproductive biology for the wider riffle-dwelling Chiloglanis is generally sparse in the literature. Data is sparse here rather than assumed; nothing specific to this species' courtship is claimed.
Breeding
There are no confirmed reports of Chiloglanis dialloi breeding in captivity, and the cache does not document its reproductive mode in the wild in detail. This is consistent with the genus as a whole: small riffle Chiloglanis are rarely if ever bred in home aquaria, and most individuals in the hobby (where they appear at all) are wild-collected rather than captive-produced. Prospective keepers should not expect to breed this species and should be honest that its conservation-sensitive, single-river wild population is the only current source of any specimens seen in trade.
In the aquarium
Chiloglanis dialloi is essentially unknown in the hobby — it is not a species with an established aquarium history, and the cache material centres on taxonomy and conservation rather than care reports. What can be said with confidence follows from its genus and its biology rather than from aquarium trial: as a rock-clinging riffle specialist, it would need strong water flow, high dissolved oxygen and a rocky substrate rather than the calm, planted layouts suited to many other small catfish, and its modest maximum size (about 2 in SL) means a small footprint is not the limiting factor — water movement and oxygenation are.
As with all Mochokidae, its skin is scaleless, so it should be treated as medication-sensitive: copper-based treatments and many standard medications should be dosed conservatively, at reduced strength, the way loaches, puffers and eels are handled. It also carries the family's stiff, serrated, locking pectoral and dorsal spines, which can snag in a net and jab the keeper — move it in a container rather than netting it directly. Given its Endangered status and essentially undocumented aquarium history, this is not a species to seek out or collect casually; any specimens in the trade should be treated as wild-collected from an already fragmented, threatened population.
Conservation
The IUCN Red List assesses Chiloglanis dialloi as Endangered (EN), assessed in 2019 under criterion B1ab(iii) for habitat fragmentation across its restricted range. The species is known only from the Moa River drainage in Guinea, with a possible presence in Sierra Leone, giving it an extremely small and fragmented distribution typical of many narrow-range West African riffle specialists.
Because its entire known population depends on a single river system, any degradation of that habitat — deforestation, siltation, damming or pollution altering the flow and oxygenation the species depends on — carries outsized risk for a fish with nowhere else to go. Species like C. dialloi illustrate why single-river catfish endemics, though rarely seen by aquarists, are often among the most conservation-urgent fish in the family.