Taxonomy & naming
Microctenopoma uelense was described by J.S. Norris and R.W. Douglas in 1995, in a paper that simultaneously erected the new genus Microctenopoma and named two species within it: M. uelense and M. nigricans. The genus was created to accommodate small African anabantids that were distinguished from the larger genus Ctenopoma by a suite of morphological and size characters. The valid name as recorded in Eschmeyer's Catalog of Fishes (Fricke, Eschmeyer & Fong) is Microctenopoma uelense Norris & Douglas, 1995; the authority is not parenthetical because the species was described directly into the genus where it currently resides.
The type locality is the Uele River drainage in the Democratic Republic of Congo. The genus Microctenopoma belongs to the family Anabantidae (the climbing perches and bushfishes), one of the families within the order Anabantiformes, which encompasses all labyrinth fishes. Within that family the African anabantids form a distinct radiation from their Asian relatives.
Morphology
Microctenopoma uelense is a small species, with males reaching a maximum of approximately 2.5 in standard length (SL) and females slightly smaller at around 2 in SL. Like other members of the genus it is a compact, somewhat laterally compressed fish with the comb-like ctenii (serrations along the preopercle) that give the genus its name — Microctenopoma meaning small comb-tooth.
Formal morphological data published in the primary description are sparse in the secondary literature. As with congeners such as M. ansorgii, the body is likely cryptically patterned for life in forested stream environments, and the species is presumed to share the rounded fins and moderately deep body profile typical of small African anabantids. Sexual differences in colour or finnage, if any, are not well characterised in the available literature; data for this species remain sparse.
Habitat
The species is recorded from the Uele River drainage and the upper and middle reaches of the Aruwimi and Itimbiri drainages, all within the middle Congo River basin of the Democratic Republic of Congo. These are broadly tropical lowland systems draining the northeastern Congo rainforest — a landscape of slow to moderately flowing forest streams, gallery forest, and seasonally inundated floodplain habitats.
Formal habitat data for M. uelense specifically are not published in readily accessible sources. By analogy with its well-studied congener M. ansorgii, which inhabits slow-flowing forest streams with dense marginal vegetation and leaf-litter substrate, M. uelense likely frequents heavily shaded, vegetated reaches where the water is warm and soft to moderately hard. As a labyrinth fish it possesses a suprabranchial organ that permits aerial respiration, allowing it to tolerate the low dissolved-oxygen conditions common in still or sluggish forest water. Temperatures in the tropical lowland Congo basin typically range from the low to upper 20s Celsius year-round.
Feeding
No specific dietary study of Microctenopoma uelense in the wild appears in the accessible literature. Small African anabantids in the genus Microctenopoma are generally regarded as carnivorous or insectivorous predators, taking worms, insect larvae, and small aquatic invertebrates opportunistically. The related M. ansorgii is documented feeding on such prey in forest-stream environments, and M. uelense almost certainly occupies a similar feeding niche given its similar size and habitat.
In captivity, small anabantids of this type accept live and frozen invertebrate foods — bloodworm, Daphnia, small aquatic worms, and brine shrimp — and can be conditioned onto high-quality small pellets or granules, though live and frozen prey are generally preferred and promote better condition.
Mating
Reproductive behaviour in Microctenopoma uelense has not been formally documented in the published literature. The genus Microctenopoma is presumed to be a bubble-nester, following the broader pattern seen across the African anabantids in Anabantidae, where males construct and guard a floating raft of mucus-bound bubbles at the water surface and court females beneath it.
Male courtship in small bubble-nesting anabantids typically involves fin displays and lateral presentation to females, with spawning taking place close to or beneath the nest. As with other labyrinth fishes, the suprabranchial organ and the tendency to occupy still, sheltered water are closely tied to the bubble-nest reproductive strategy, which concentrates the oxygen-rich layer at the air–water interface around developing eggs.
Breeding
No captive breeding accounts for Microctenopoma uelense are documented in sources available for this article, and the species is essentially absent from the mainstream aquarium trade. Based on the reproductive biology of congeners, breeding is presumed to follow the bubble-nesting pattern: the male builds a nest of air bubbles at the surface, often anchored to floating vegetation or a sheltered corner of the tank, and the pair spawns beneath it with the male collecting and depositing fertilised eggs into the nest.
The male is expected to guard the nest and fry. Spawning water conditions for Congolese forest-stream anabantids generally call for warm, soft, slightly acidic to neutral water, subdued lighting, and dense surface or floating plant cover to support nest construction. Given the very limited availability of this species, breeding reports from hobbyists remain essentially non-existent; data for this species are sparse.
In the aquarium
Microctenopoma uelense is essentially unavailable in the mainstream aquarium hobby. The species is not commercially bred and rarely, if ever, appears in trade lists; wild-caught specimens would require export from the Democratic Republic of Congo, where collection infrastructure for this obscure drainage species is minimal. Husbandry recommendations are therefore extrapolated from congeners and from general principles for small African anabantids.
A well-planted species tank with soft, slightly acidic to neutral water, a temperature in the range of 72–81 °F, and minimal water flow would suit a fish from sheltered forest streams. Surface access is essential for labyrinth fish; a tight-fitting lid prevents escape and reduces temperature drops at the surface that can stress the suprabranchial organ. Small live and frozen foods are the recommended dietary staple. As a small, probably retiring species, M. uelense would benefit from a quiet setup with gentle tankmates of comparable size, if kept with other species at all.
Conservation
Microctenopoma uelense has not been evaluated by the IUCN Red List and carries a status of Not Evaluated (NE). FishBase records the species as present in the Uele, upper and middle Aruwimi, and Itimbiri drainages of the Democratic Republic of Congo — a region subject to ongoing pressures from deforestation, artisanal mining, and agricultural expansion in the broader Congo basin, though the specific impact of these pressures on M. uelense is undocumented.
The species' restricted range and low profile in the hobby mean that no conservation programmes, captive assurance colonies, or systematic monitoring programmes are known to exist for it. Its obscurity is itself a kind of vulnerability: a species that is unknown to science beyond its original description, absent from trade, and lacking any IUCN evaluation has no documented baseline against which to measure population change. A formal assessment and field surveys in the type drainage would be the natural first step in understanding its status.