Taxonomy & naming
Leporinus bistriatus was described by the Brazilian ichthyologist Heraldo Britski in 1997. It belongs to the family Anostomidae, the headstanders, within the order Characiformes, and to the large genus Leporinus, whose valid membership is governed by the Catalog of Fishes (Eschmeyer, California Academy of Sciences). The genus name derives from the Latin lepus (hare), an old allusion to the two prominent incisor-like teeth at the front of the jaw, echoed in the family's broader dental pattern of chisel-like teeth suited to scraping rather than piercing.
The species epithet bistriatus ("two-striped") refers to the dark longitudinal banding pattern on the flanks, a common motif across the genus that gives rise to the trade name "black-banded leporinus" for this and similar-looking species. As with many Leporinus, field identification against close relatives in the same river system rests on precise counts of scales, fin rays and the exact number and placement of body bars, characters documented in Britski's original description rather than in casual hobby literature.
Morphology
Leporinus bistriatus has the classic headstander build shared across the genus: an elongated, roughly cylindrical to laterally compressed body, a small subterminal mouth set low and slightly underslung on a blunt snout, and a forked tail. The mouth carries the genus's characteristic chisel-edged incisors, adapted for scraping algae and biofilm from hard surfaces rather than for grasping prey.
FishBase records a maximum published size of 5.5 in standard length and 52.81 g for the species — modest for the genus, in which some relatives such as L. fasciatus reach roughly 12 in total length. Colouration follows the "black-banded" pattern implied by the species name: dark vertical or diagonal bars on a lighter silvery-to-olive body, a pattern that provides some camouflage against submerged wood and root tangles in its home river. No reliable external difference between the sexes has been documented for this species.
Habitat
Leporinus bistriatus is known from the Tocantins River basin in Brazil, a major Amazon-basin tributary system. Within it the species is a benthopelagic fish, occupying the water column near structure rather than the open mid-water or the substrate itself, consistent with its head-down grazing habit along wood, rock and root surfaces.
Detailed water-chemistry data specific to this species were not found in the source material used for this article; broadly, Tocantins basin waters are warm, tropical lowland river conditions, and data is sparse enough that specific pH and hardness figures should not be assumed rather than stated as documented.
Feeding
Leporinus bistriatus is an omnivorous grazer. Aquarium and care-guide sources describe the diet as including vegetative matter alongside worms, insects and crustaceans, consistent with the head-down aufwuchs-grazing behaviour typical of the genus — picking algae and biofilm from submerged wood and rock while also taking small invertebrates opportunistically.
In the aquarium this translates to a need for a vegetable-forward diet: algae wafers, blanched vegetables and quality herbivore-leaning pellets, supplemented with some protein such as bloodworm or brine shrimp. As with many Leporinus, soft-leaved live plants are at real risk from grazing and should not be assumed safe in a planted tank housing this species.
Mating
No courtship behaviour specific to Leporinus bistriatus was found in the source material used for this article. Hobby literature notes the species is described as an active, gregarious swimmer in the wild, but detailed spawning or pairing behaviour has not been documented — data is sparse here, and it should be treated as such rather than inferred from other Leporinus species.
Breeding
Leporinus bistriatus is not commonly bred in captivity, and detailed accounts of its reproduction were not found in the source material. FishBase describes the genus pattern for related headstanders as egg-scattering in densely weedy areas, with no parental care of the eggs or fry, and hobby sources note this species specifically is not commonly bred in the home aquarium. Some Leporinus are farmed commercially, but there is no indication this smaller, more localised species is among them; keepers should not expect to breed it reliably at home.
In the aquarium
At a documented maximum of 5.5 in SL, Leporinus bistriatus stays smaller than many of its genus-mates, but it should still be housed in a spacious, well-covered tank with driftwood and rockwork to graze, open swimming room, and robust filtration for its active habits. As with other Leporinus, a fin-nipping tendency has been noted for the genus, so tankmates should be chosen with care — fast, robust, non-filamentous-finned companions are safer choices than slow or long-finned fish.
The species is an active, gregarious swimmer in the wild, which suggests it does best kept in a group rather than alone, though specific numbers are not documented. Soft-leaved plants should be considered at risk given the species' vegetative grazing habit, and keepers should budget tank size and décor around a fish that will graze constantly and swim actively rather than sit still.
Conservation
The IUCN Red List assessed Leporinus bistriatus as Near Threatened in an assessment dated 7 November 2018, tied to its restricted known range within the Tocantins River basin of Brazil. A geographically narrow distribution in a single major river system leaves a species more exposed to localised pressures — damming, water-quality change and habitat modification are the general pressures relevant to Tocantins basin fish, though species-specific threat data beyond the Near Threatened listing was not found in the source material.
Given the Near Threatened status, this is a species where trade and keeping should not be assumed to draw on a large, resilient wild population, even though specific harvest data was not available in the sources used here.