Taxonomy & naming
Ctenopoma weeksii was described by the Belgian ichthyologist George Albert Boulenger in 1896, in a paper on new fishes from the upper Congo published in the Annals and Magazine of Natural History (series 6, volume 17, pages 309–311). The type material was collected from the Congo River and Boulenger placed it in the genus Ctenopoma, where it has remained under that name ever since. A subsequent synonym, Anabas oxyrhynchus Boulenger, 1902, was later referred here but the 1896 name has priority.
The genus Ctenopoma is placed in the family Anabantidae — the true climbing perches and bushfishes — and, like all members of that family, the species is an obligate air-breather equipped with a suprabranchial labyrinth organ. Within Ctenopoma, weeksii belongs to a group of predatory bushfishes distributed across the Congo basin, distinct from the more widespread and less predatory C. acutirostre complex. Vernacular names recorded in reference databases include Mottled Ctenopoma, Marbled Climbing Perch, Sharpnose Climbing Perch, and the German Pfauenaugen-Buschfisch.
Morphology
Adults reach approximately 4.5 in total length according to FishBase, with Seriously Fish citing a standard length of around 4 in. The body is elongate and moderately compressed, with the slightly pointed snout that earns the common name 'sharpnose'. The caudal peduncle is robust and the fins are rounded, a typical Ctenopoma build suited for ambush rather than open-water pursuit.
Base colouration is a warm brown with irregular darker markings along the flanks, often coalescing into a loose reticulated or marbled pattern. A single darker spot is typically present on each flank. When startled or displaying, the fish can switch rapidly to a dramatically mottled appearance — a camouflage mechanism also seen in other members of the genus. Sexual dimorphism is subtle but real: males carry more pronounced ctenoid (toothed) spine patches on the gill covers and at the base of the caudal peduncle, a feature used in both species identification and sexing.
Habitat
Ctenopoma weeksii is distributed across the middle Congo River basin in the Democratic Republic of the Congo, with records also from the upper Congo drainage. It occupies sluggish and still waters — pools, backwaters, lagoons, and swamps — where dissolved oxygen can be low and cover is dense. The suprabranchial labyrinth organ allows the species to supplement gill respiration by breathing atmospheric air, which is critical in the hypoxic conditions of these stagnant or slow-moving habitats.
The species is crepuscular or nocturnal in activity and strongly associated with dim, vegetated microhabitats where its mottled colouration provides effective camouflage among leaves and debris. Water chemistry across its range spans a moderately broad range: FishBase records temperatures of 75–82 °F, pH 6.2–7.2, and a hardness of 4–15 dH, reflecting the soft-to-moderate, slightly acidic to neutral character of Congo basin lowland waters. It is not a specialist of extreme blackwater and hobbyist sources describe it as undemanding regarding water chemistry.
Feeding
Ctenopoma weeksii is a carnivorous ambush predator. In the wild it feeds on small fish, invertebrates, and aquatic insects, lying motionless among vegetation and debris until prey ventures within range. The pointed snout and large mouth are adaptations for capturing mobile prey with a rapid lunge.
In the aquarium the species is initially reluctant to take prepared foods and does best started on live or frozen alternatives: earthworms, mealworms, prawn, bloodworm, and mussel are all documented as accepted foods. With patience, many individuals can be transitioned to high-protein frozen and sinking pellet foods. Because the fish is a lurking predator rather than an active forager, feeding sessions should be conducted in low light and with patience — placing food near the fish's resting spot rather than expecting it to compete openly at the surface.
Mating
Ctenopoma weeksii is an open-water egg-scatterer. Spawning takes place near the surface, where a receptive pair embrace in the characteristic anabantoid clasp and release buoyant or semi-buoyant eggs that float up into surface vegetation or drift among floating plant matter. There is no bubble nest and no parental involvement in the preparation of a spawning site.
Sexual dimorphism in this species is expressed principally through the ctenoid spine patches on the males' gill covers and caudal peduncle area — traits that likely play a role in male-male assessment or courtship signalling. As in other Ctenopoma, males may display by flaring gill covers and spreading fins, though formal observation of courtship behaviour in the literature is limited. Conditioning adults on varied live and frozen foods promotes spawning readiness.
Breeding
Spawning pairs embrace at or near the water surface and release eggs into floating vegetation; the eggs are buoyant and hatch in approximately 48 hours under typical temperatures of 79–82 °F. The fry become free-swimming quickly after hatching and are initially very small, requiring appropriately fine first foods.
No parental care is provided at any stage — adults will consume both eggs and fry if not removed. Standard practice is to allow the spawning to proceed, then transfer the adults out or net the surface spawn into a separate rearing container. The fry can be started on infusoria or commercial liquid fry foods, progressing to newly hatched brine shrimp as they grow. The species has been bred in captivity under medium water conditions without particular difficulty, and is considered one of the more accessible Ctenopoma species for the breeding hobbyist.
In the aquarium
Ctenopoma weeksii is best kept in a dimly lit, well-planted aquarium with plenty of structure — bogwood, leaf litter, and dense vegetation provide the cover the species requires to feel secure and display its most interesting behaviours. A tank of 20 US gal or more suits a single specimen or a pair; the species is largely sedentary and does not need a large open swimming area, but the tank should have stable, clean water with gentle filtration. Access to the surface for air-breathing is essential.
It is a predator and will consume any tankmates small enough to fit in its mouth, so companions must be chosen carefully and sized accordingly. Robust, similarly sized African species are the best pairing; small tetras, livebearers, or juvenile fish of any species should be avoided. Water chemistry is flexible — the species tolerates pH 6.2–7.2 and moderate hardness without difficulty — and it is described by hobbyist sources as undemanding in this respect. Feeding requires patience: live or thawed frozen foods placed near the fish's hiding spot in subdued light, gradually building toward a more varied frozen diet. Despite the patience required, the species' cryptic beauty, shifting colour pattern, and calm temperament make it an appealing centrepiece for an African biotope setup.
Conservation
Ctenopoma weeksii is assessed as Least Concern (LC) on the IUCN Red List, reflecting its occurrence across a broad portion of the Congo River basin with no evidence of major population decline. The Congo basin supports one of the largest and most intact tropical river systems in the world, and many of its endemic fish species — including this one — remain relatively secure within that vast watershed.
No specific conservation measures are recorded as targeting this species. The primary pressures across the Congo basin — habitat conversion, artisanal fishing, and ongoing deforestation in upland catchments — are general threats to the system rather than species-specific ones. The species is occasionally available in the ornamental trade, but collection pressure appears well within sustainable limits given its distribution. Hobbyists sourcing captive-bred individuals reduce even that modest impact.