Coptostomabarbus is a small genus of barbs (family Cyprinidae) from south-central Africa, recorded in the atlas across the upper Congo and Zambezi river systems - the Democratic Republic of the Congo, Angola, Botswana, Zambia, and Zimbabwe. The atlas covers 2 species, both known as the upjaw barb (C. bellcrossi and C. wittei), running a small 1–1.5 in. The genus name and common name both point to its defining feature: a distinctly upturned, protruding lower jaw, an adaptation suited to picking food near the surface or in midwater rather than grubbing along the bottom the way many barbs do.
Hobby presence is minor - this is a specialist barb-keeper's genus rather than a fish seen in general retail. Neither atlas species is currently flagged as threatened, with one Least Concern and one Not Evaluated, though the floodplain and river habitats of the upper Zambezi and Congo systems remain broadly under-surveyed for smaller fish like this.