Taxonomy & naming
Ctenopoma multispine was described by the German naturalist Wilhelm Peters in 1844. The valid name as recognised in Eschmeyer's Catalog of Fishes is Ctenopoma multispine Peters, 1844; the specific epithet multispine refers to the many spines (Latin: multi, many; spina, spine or thorn) that characterise the species' serrated preopercle and lateral-body margins, a feature common to several Ctenopoma and used in older literature to distinguish them.
The genus Ctenopoma is placed in the family Anabantidae (the true climbing perches and African bushfishes) within the suborder Anabantoidei, which unites all the labyrinth fishes — those capable of aerial respiration via the suprabranchial (labyrinth) organ. FishBase places C. multispine in the tribe Ctenopomini. The genus spans most of sub-Saharan Africa, with species occupying everything from forest streams to open floodplains and swamps; C. multispine is among the more widespread and ecologically generalist members.
Morphology
Ctenopoma multispine is a moderately large bushfish reaching up to 5.5 in standard length according to FishBase, making it one of the bigger species in the genus. The body is moderately compressed laterally and oval in profile, typical of the genus, with a large, oblique, upturned mouth suited to surface and mid-water prey capture. The preopercle and interopercle bear rows of small spines — the character that gives the species its name — and the ctenoid body scales give the flanks a rough texture.
Colouration is cryptic and variable: the body is generally brownish to greyish-brown with an irregular pattern of faint darker blotches or mottling that provides camouflage among submerged vegetation and leaf litter. A dark spot near the base of the tail is common in juveniles and may persist in adults. Fins are plain to lightly spotted. There is no dramatic sexual colour dichromatism, and sexing live fish is best accomplished by the shape of the genital papilla, or by the more rounded belly profile of ripe females.
Habitat
Ctenopoma multispine occurs in the Congo River basin, including drainages in Angola and the Democratic Republic of Congo. It inhabits vegetated riverine backwaters, floodplain lagoons, swamps, and isolated seasonal pans — slow to still-water environments with abundant aquatic and emergent vegetation. FishBase describes it as a benthopelagic species of tropical, shallow-water habitats with a preference for areas with dense plant cover that provide both ambush sites and shelter.
Water conditions across its range include temperatures around 75 °F and a moderately broad pH range of roughly 6.0–7.5, with water hardness spanning soft to moderately hard (dH 5–20). As a true labyrinth fish it can breathe atmospheric air directly at the surface, allowing it to persist in warm, stagnant, oxygen-depleted conditions that would exclude gill-only fishes. FishBase notes that the species can endure drought by migrating overland between water bodies — a classic anabantoid survival strategy.
Feeding
Ctenopoma multispine is a predatory fish that feeds on small aquatic invertebrates, insects, freshwater shrimps, and small fish. FishBase records its diet as including small creatures of these categories. Its large, oblique mouth and ambush-style hunting posture — lying still among vegetation before lunging — are well suited to taking live prey at or near the surface and in the water column.
In the aquarium it will accept live and frozen foods readily: small fish, earthworms, bloodworm, brine shrimp, and other meaty invertebrate foods. Adapting larger individuals to dried foods can be slow; a predominantly meaty diet suits them best. The species is an opportunistic predator, so anything small enough to swallow will be treated as prey — a consideration when selecting tankmates.
Mating
Ctenopoma multispine is an open-water egg-scatterer: breeding pairs or groups congregate and release buoyant, unguarded eggs into the water column without constructing any nest structure and without providing any parental care following spawning. FishBase notes that the species congregates in groups to breed and that the eggs are scattered and not guarded, confirming the open-water egg-releasing strategy.
As with most egg-scattering anabantoids, courtship likely involves some lateral display and parallel swimming by the pair, with males showing off to females and possibly competing with rival males. The buoyancy of the eggs suggests they drift toward the surface or float freely until hatching, relying on dispersion rather than parental protection as a survival strategy.
Breeding
Reports of aquarium breeding for Ctenopoma multispine are scarce in the hobby literature, and the species is rarely deliberately bred in captivity. Based on its confirmed open-water egg-scattering mode, no specialised spawning structure is required: a well-planted, spacious aquarium with ample cover and a slight temperature increase may condition fish toward spawning. Eggs are buoyant and unguarded; once released, adults show no interest in them and may consume any they encounter.
Fry will be small and require appropriately tiny first foods. Raising the young of a predatory fish of this size typically requires careful management to prevent cannibalism among fry of different sizes as they develop. Given the limited captive breeding documentation, most of what is known about the species comes from field biology rather than controlled aquarium observation.
In the aquarium
Ctenopoma multispine is an infrequently kept species suited to experienced aquarists with an interest in predatory African fish rather than beginners seeking a community display fish. Its size — up to 5.5 in — and predatory nature mean that small tankmates will be consumed; it is best housed with fish of similar size that are too large to be swallowed. Larger cichlids, larger characins, or other robust mid-sized African fish are the most practical companions.
Housing should include ample cover in the form of caves, driftwood, and dense planting, which suits the species' ambush hunting style and helps it feel secure. Lighting can be subdued. Water quality within a pH of 6.0–7.5 and temperatures around 75 °F are appropriate; the species tolerates a reasonable range. Surface access is important — like all labyrinth fish it must be able to breathe air directly, and a tight-fitting lid is advisable given anabantoids' tendency to jump. Feeding is best managed with live or frozen meaty foods, and a varied diet keeps the fish in good condition.
Conservation
Ctenopoma multispine is assessed as Least Concern (LC) on the IUCN Red List (assessment version 3.1). The global assessment reflects the species' wide distribution across the Congo basin and its apparent tolerance of a broad range of still and slow-water habitats, with populations considered stable in suitable habitat across its range in Angola and the Democratic Republic of Congo.
The SANBI Species Status Assessment (January 2017) treated the species as Not Evaluated (NE) at a regional South African level, noting its benthopelagic habit and occurrence in vegetated riverine backwaters, floodplain lagoons, swamps, and isolated pans. No major conservation threats are currently flagged for this species globally, though habitat degradation of Congo basin floodplain and wetland systems remains an ongoing concern for the wider community of species they support.