Taxonomy & naming
Nannocharax dageti was described in 2014 by Jerep, Vari and Vreven as a new species from the southern tributaries of the Congo River basin in the Democratic Republic of the Congo and Zambia, with an additional population in the Kafue River of the middle Zambezi basin. It belongs to the genus Nannocharax, a large assemblage of small, elongate, benthic African characins within the family Distichodontidae — the same family that contains the much larger, deep-bodied Distichodus and the grazing citharinids are its close relatives within the broader citharinoid lineage. The species epithet honours Dr. Jacques Daget (1919–2009), the French ichthyologist long associated with the Muséum National d'Histoire Naturelle in Paris and one of the foundational figures in the study of West and Central African freshwater fishes.
As with much of the Nannocharax radiation, species boundaries rest on fine anatomical detail rather than obvious external differences, and N. dageti is distinguished from its close relatives by a combination of colour pattern and meristic counts (see Morphology). It is treated as allopatric — occupying its own river systems without overlapping — relative to other Nannocharax species in the southern Congo tributaries. There is no common or trade name in general use for this species; it has essentially no presence in the aquarium hobby, and the name below is used simply as a working English handle rather than an established vernacular.
Morphology
Nannocharax dageti is a small, slender, bottom-oriented characin, with FishBase recording a maximum published standard length of just 1.5 in — among the smallest members of its family. Its original description notes dark, rounded blotches that overlap a midlateral longitudinal stripe running along the flank, a pattern used alongside other characters to separate it from related Nannocharax species in the region. The dorsal-fin origin sits anterior to the pelvic-fin origin, and the species carries 40–43 scales in an incompletely pored lateral-line series — technical counts that matter for identification but are not something a casual observer would use in the field.
Like other Nannocharax, the overall body plan is built for a life spent close to the substrate: an elongate, only moderately compressed body, a small subterminal or underslung mouth suited to picking food from surfaces rather than seizing prey in open water, and fins proportioned for short, controlled movements rather than sustained cruising. No data on sexual dimorphism in colour or shape has been documented for this species.
Habitat
The species is known from the Kasai, Lualaba and Luapula rivers in the middle and upper Congo River basin, and from the Kafue River in the middle Zambezi basin — a range that spans two of Africa's great river systems without, as far as is documented, connecting them directly. FishBase describes it as benthopelagic, meaning it lives and forages near the bottom rather than in open midwater, consistent with the small, substrate-picking body plan typical of the genus.
No species-specific water-chemistry data has been published for N. dageti, but the wider Congo basin habitat that Distichodontidae occupies is generally warm and often acidic to strongly acidic, tannin-stained blackwater with low mineral content — some Congo tributary readings run as low as pH 4–4.5 with very low conductivity — though whitewater and clearwater stretches also exist across this vast system. Given the lack of a direct record for this species, any water parameters offered for the aquarium should be treated as a reasonable inference from the family and region rather than a documented fact.
Feeding
Published diet data specific to Nannocharax dageti is not available. More broadly, Nannocharax species are small benthic characins that feed on benthic invertebrates in the wild — picking small aquatic insect larvae, worms and other invertebrates from the substrate and leaf litter rather than grazing algae or plant matter, unlike their much larger Distichodus relatives.
Aquarium reports for related Nannocharax species describe a preference for small live and frozen foods such as bloodworm and Daphnia, with most species in the genus reluctant to take dry flake or pellet food readily. In the near-total absence of care data for N. dageti itself, this pattern is the best available guide, offered as an inference from its relatives rather than a documented account of this species.
Mating
No courtship or spawning behaviour has been documented for Nannocharax dageti. FishBase records no maturity length (Lm) data for the species, reflecting how little research attention this small, range-restricted characin has received since its 2014 description. Nothing reliable can be said here beyond noting the gap in the record rather than guessing.
Breeding
Breeding in Nannocharax dageti is not documented in the wild or in captivity, and no aquarium care record for the species has been found. This fits the wider pattern for African characins in Distichodontidae: Distichodus and the citharinids are egg-scattering broadcast spawners that are rarely, if ever, bred at home, and Nannocharax as a genus has essentially no established captive-breeding record either. Rather than assign a speculative mode, the honest statement is that this species' reproductive biology remains unstudied outside its taxonomic description.
In the aquarium
Nannocharax dageti is, by size alone, one of the smallest characins one could keep — a fully grown adult reaches only around 1.5 in — but it is essentially absent from the aquarium trade and from hobbyist literature, and no established care regimen exists for it. What can be said comes from its genus: Nannocharax species are shy, bottom-dwelling fish best suited to a heavily furnished nano or small tank with fine leaf litter, soft acidic water and gentle flow, kept in a group rather than alone, and offered small live or frozen invertebrate foods rather than dry food.
Given the total lack of documented husbandry for this specific species, anyone attempting to keep it would be working from first principles based on its habitat and its genus relatives, not from an established protocol — and given its restricted range and apparent rarity, wild collection for the trade would carry real conservation weight that a keeper should weigh carefully.
Conservation
Nannocharax dageti has not been assessed by the IUCN Red List, and no dedicated conservation evaluation is currently available (Not Evaluated). Given its narrow, specific range across a handful of river systems in the DRC and Zambia — the Kasai, Lualaba and Luapula rivers plus the Kafue River — and the general lack of research attention paid to it since its 2014 description, this is best understood as a data-poor, likely under-studied species rather than one known to be secure.
No commercial trade, targeted fishery or aquarium demand has been documented for this species, which likely limits direct pressure on its populations; the more relevant long-term concerns are the same ones facing freshwater fish broadly across the Congo and Zambezi basins — habitat change, water-quality pressure and, in the Zambezi system, damming and flow regulation. Without a formal assessment, its true conservation status remains unknown.