Taxonomy & naming
Tetraodon duboisi was described by the Belgian ichthyologist Max Poll in 1959, in the Annales du Musée du Congo Belge (volume 71, art. 3, p. 116, Pl. 21 figs. 1A–1B). The holotype (MRAC 119888) and a paratype (MRAC 118576) are held at the Royal Museum for Central Africa in Tervuren, Belgium; the type locality is Kinshasa, Stanley Pool, Democratic Republic of Congo.
The Catalog of Fishes (Eschmeyer, California Academy of Sciences — the authority for valid names in this atlas) recognises the valid combination as Tetraodon duboisi Poll, 1959. The genus Tetraodon has undergone significant revision since the twentieth century: what was once a near-cosmopolitan genus has been restructured so that Tetraodon is now effectively African-only, with the Asian species redistributed among Dichotomyctere (the brackish green-spotted and figure-eight puffers), Pao (Mekong river puffers), Leiodon and others. The African Tetraodon remain: the enormous Mbu (T. mbu), the Congo puffer (T. schoutedeni), the Fahaka (T. lineatus), the miurus and pustulatus, and this species, T. duboisi.
The species epithet honours someone named Dubois, though the dedicatee is not elaborated in the original description as recovered from the catalog record. The common names "Dubois's puffer" and "Malebo puffer" are both current in the hobbyist trade; the latter refers to the Pool Malebo (Stanley Pool), the only confirmed locality for the species.
Morphology
Tetraodon duboisi reaches a maximum total length of approximately 3.5 in, making it a small to mid-sized member of the African Tetraodon. Like all pufferfish it lacks true scales, relying instead on skin that may be smooth or covered with small prickles (the prickles are typically concealed except when the fish is inflated). The body is rotund and torpedo-shaped, with the large head and wide-set eyes characteristic of the genus.
The four fused teeth that give the family Tetraodontidae its name form a prominent beak — two fused upper plates and two lower — which is hard, continuously growing, and capable of crushing snail shells and crustacean exoskeletons. Detailed published coloration descriptions for T. duboisi specifically are sparse in the accessible literature; the closely related African Tetraodon typically show mottled or spotted brown, olive and cream patterning that provides camouflage on riverine substrates, and aquarist reports suggest T. duboisi follows a similar cryptic pattern. The species is internally oviparous (egg-laying).
Because T. duboisi lacks scales and true gill covers, it shares the general puffer sensitivity to medication — particularly copper-based treatments — and should be handled with care given the tetrodotoxin (TTX) present in its skin and organs.
Habitat
All confirmed records of Tetraodon duboisi come from Pool Malebo (Stanley Pool), a wide, island-studded lake-like expansion of the Congo River near Kinshasa and Brazzaville. The Pool sits at approximately 951 ft elevation, fed by the Congo — one of the world's largest rivers by discharge — and holds characteristic Congo basin water: warm, soft to moderately soft, and near-neutral in pH. The cache parameters place the species in water of 79–82 °F and pH 7.0–7.5, consistent with the broader lower Congo conditions.
Pool Malebo is renowned in ichthyology as a centre of endemism: the extraordinary speed and turbulence of the Congo downstream of the Pool has produced some of the most species-rich, isolated fish communities in Africa. Whether T. duboisi is genuinely confined to the Pool or occurs more widely in adjacent lower-Congo channels is not established in the published record — the survey record is sparse, and the political instability of the DRC has limited fieldwork for decades. The species is classified as a freshwater endemic; it does not require or tolerate brackish conditions.
Feeding
Tetraodon duboisi is a highly predatory invertivore. Aquarist accounts describe a fish that readily takes krill, shrimp, crayfish and crab, as well as occasional feeder fish — a diet consistent with the crushing-beak morphology of all Tetraodon, which are adapted to breaking through hard shells. In the wild, snails and freshwater molluscs are presumed to form a significant part of the natural diet, as they do for most African puffers.
The beak of a pufferfish never stops growing. If the animal is fed exclusively on soft foods — freeze-dried pellets, worms, or processed items alone — the beak will overgrow, eventually preventing normal feeding and requiring veterinary intervention. Hard-shelled prey (snails, small crustaceans, whole shellfish) are mandatory, not optional, for long-term health. In captivity this species should receive a variety of suitably sized crustaceans and molluscs as the core diet, with other meaty items as supplement.
Mating
Captive breeding of Tetraodon duboisi has not been documented in the available literature or among the small community of aquarists who have kept the species. The species is noted as oviparous (egg-laying), but the details of courtship, mate selection, spawning site preference and pair behaviour in this species are unknown.
For context within the genus: the closely related Congo puffer (T. schoutedeni) — the most frequently bred African Tetraodon in captivity — is a substrate spawner in which the male guards the eggs after spawning. Whether T. duboisi follows the same pattern cannot be confirmed from the available data. Aquarists working with the species report solitary, highly aggressive individuals that do not tolerate conspecifics outside of any potential breeding interaction, suggesting the fish is not a social or colonial spawner.
Breeding
No verified captive breeding of Tetraodon duboisi has been recorded as of the date of this article. The species is rare in the hobby — specimens occasionally appear through importers supplying African oddities from the DRC — and the combination of aggressive temperament, uncertain sexing criteria, and limited hobbyist experience means that any account of breeding this species remains anecdotal or absent.
By analogy with related African Tetraodon, the reproductive mode is likely substrate spawning with eggs deposited on or near the bottom, and parental care by one or both parents is plausible but unconfirmed for this species. Aquarists interested in attempting to breed T. duboisi would be working at the frontier of husbandry knowledge; documenting any successful breeding would constitute a significant contribution to understanding the species.
In the aquarium
Tetraodon duboisi is a demanding and specialist fish, suitable only for experienced aquarists prepared to meet its needs. It is solitary and highly aggressive — it should be kept alone or, at most, one per tank with robust, dissimilar species that it cannot bite; fin-nipping is certain with anything that shares the water. A minimum tank volume of around 30 US gal for a single adult is indicated by hobbyist accounts, with strong filtration and regular large water changes to manage the considerable waste output typical of heavily fed puffers.
Water parameters should mirror lower Congo conditions: temperature 79–82 °F, pH 7.0–7.5, soft to moderately soft water. Moderate current suits the natural environment. Diet must include hard-shelled invertebrates — snails, shrimp, crayfish, small crabs — on a regular basis to keep the beak worn; without these, beak overgrowth becomes a serious veterinary problem. Because puffers are scaleless and lack functional gill covers, copper-based medications are toxic to this species and must never be used; other medications should be dosed conservatively. Puffers inflate by gulping water as a defence and must never be lifted out of the water into air, as an air-filled body is extremely difficult for the fish to expel and can be fatal. The skin and organs of pufferfish carry tetrodotoxin; handlers should wash hands after contact and the fish should never be consumed.
With appropriate care, T. duboisi is reported as a characterful, interactive animal — puffers generally make eye contact with their keepers and can become individually recognisable — but the combination of aggression, specialist diet, medication sensitivity and scarcity makes it a fish for dedicated specialists rather than the general community tank.
Conservation
The IUCN Red List assesses Tetraodon duboisi as Data Deficient (DD), reflecting the fundamental lack of population data for a species known almost entirely from one locality — Pool Malebo on the Congo River — in a region where sustained scientific fieldwork has been disrupted for decades by political instability in the Democratic Republic of Congo.
Data Deficient status does not mean the species is necessarily secure: some observers have speculated that real-world conditions in the lower Congo — pollution from Kinshasa's expanding urban footprint, artisanal fishing, and the near-absence of baseline survey data — could mean the species is more threatened than its formal status suggests. The Congo basin as a whole faces escalating pressure from habitat modification, mining runoff, and overfishing, and narrow-endemic species like T. duboisi are inherently vulnerable to localised disturbance at their sole known locality.
Capture for the aquarium trade is likely a minor pressure given the species' rarity in commerce, but the absence of established captive breeding means that any trade specimens must originate from wild collection. A credible assessment of the species' conservation status will require systematic survey work in Pool Malebo — work that has not been feasible under recent conditions in the region.