Holopristis is a small genus of South American tetras (family Characidae) distributed across Amazon and Guiana Shield drainages in Brazil, Peru, Suriname, Colombia, French Guiana, and Guyana. The atlas covers 3 species — falsa, haraldi, and ocellifera — ranging from about 1–2 in, small, slender schooling characins typical of blackwater and clearwater forest streams.
Species now placed in Holopristis were long classified in the far larger genus Hemigrammus, and the group's aquarium reputation still traces back to that history: Holopristis ocellifera is the fish long sold and kept as the 'Head-and-taillight Tetra,' a durable, easy-to-keep schooling characin recognizable by the glowing spots near its eye and tail base that made it a mainstay of community aquariums for decades. H. falsa (also called the Head-and-tail-light Fish) is closely similar in appearance; H. haraldi is the least documented of the three. Two of the three species are rated Least Concern, with the third not yet evaluated.