Taxonomy & naming
Leporinus desmotes was described by the American ichthyologist Henry Weed Fowler in 1914. It belongs to the family Anostomidae — the headstanders — within the order Characiformes, and to the genus Leporinus, one of the largest genera in the family, distinguished by an elongate, sub-cylindrical body, a small terminal-to-subterminal mouth armed with chisel-like incisor teeth suited to grazing, and the oblique, head-down posture the family is named for.
The Catalog of Fishes (Eschmeyer, California Academy of Sciences) is the governing authority for the valid name and combination; GBIF records confirm the binomial as Leporinus desmotes Fowler, 1914 within Anostomidae. The genus name Leporinus derives from the Latin lepus/leporinus, "hare-like," a reference to the protruding, rabbit-like incisor teeth shared across the genus; the specific epithet desmotes is not detailed in the cited sources, so it is left unglossed here rather than guessed at.
Morphology
Leporinus desmotes has the classic elongate, laterally compressed headstander body plan, with a small, downturned mouth set with the incisor-like teeth typical of the genus, built for scraping algae and biofilm rather than for grabbing prey. FishBase records a maximum length of 8.5 in SL, a solid mid-sized headstander rather than one of the genus's smaller species — an adult fish needs a correspondingly large aquarium.
Colouration and fin pattern are not detailed in the cited sources for this species; as in other Leporinus, expect a silvery-to-olive ground colour, though keepers should not assume a specific banding or blotch pattern without a direct source. Sexes are not documented as externally distinct in the available material.
Habitat
Leporinus desmotes is native to the Rupununi river basin, spanning Guyana, Suriname and adjacent northern Brazil — a Guiana Shield drainage of clear-to-blackwater rivers, savannah channels and seasonally flooded wetlands. iNaturalist occurrence records support this Rupununi-basin distribution across the shared border region of the three countries.
FishBase gives water conditions of pH 6.5–7.2, general hardness 5–18 dH, and a tropical temperature range of 72–79 °F — moderately soft to moderately hard, near-neutral water rather than extreme soft blackwater, consistent with a mixed clearwater/blackwater Guiana Shield system rather than a single extreme water type.
Feeding
Leporinus desmotes is an omnivorous grazer: FishBase describes a diet of algae and aquatic invertebrates including insects, Tubifex and Daphnia, gleaned in the oblique, head-down posture characteristic of the family as the fish works over wood, stone and other submerged surfaces. AquaInfo's aquarium-care notes reinforce this, describing the species as taking mainly vegetable food — lettuce and vegetable-based dry food — alongside live foods such as Tubifex and Daphnia.
In the aquarium this translates to a vegetable-forward diet: blanched vegetables, spirulina-based flake or pellet, and algae wafers, supplemented with modest amounts of live or frozen invertebrate food. AquaInfo specifically notes the species is not suitable for planted tanks, since a grazing headstander of this size will treat soft aquarium plants as another food source.
Mating
No courtship or spawning behaviour for Leporinus desmotes is documented in the cited sources. As in other headstanders, any pairing or spawning behaviour would be expected to be brief and not preceded by elaborate courtship, but this is not confirmed for this species specifically and should not be presented as observed fact.
Breeding
Leporinus desmotes is not documented as bred in the aquarium hobby in the cited sources. As with most Leporinus, the expected mode is an egg-scattering strategy with no parental care, consistent with the wider pattern in the genus (a handful of Leporinus and Anostomus species have been spawned by hobbyists or farmed commercially, but most are not routinely bred at home) — but no breeding account specific to this species was found, so keepers should treat home breeding as effectively undocumented rather than assume it follows the genus norm without evidence.
In the aquarium
AquaInfo's care notes describe Leporinus desmotes as preferring roots, driftwood and stones for cover, with open swimming space in the centre of the tank — set up the aquarium with solid structure rather than dense planting, since the species is explicitly noted as unsuitable for planted tanks. At a documented maximum of 8.5 in, this is a mid-sized, active fish that needs a genuinely large aquarium as an adult, not a species to size for its juvenile form at purchase.
As with many Leporinus and Anostomus relatives, keepers should be alert to territoriality and fin-nipping tendencies as the fish matures, particularly toward slower or long-finned tankmates; the cited sources describe it as a peaceful schooling fish, but this genus-wide caution is worth heeding regardless. Feed a vegetable-forward diet (see Feeding) and provide well-oxygenated, near-neutral water in the pH 6.5–7.2, 72–79 °F range documented by FishBase.
Conservation
Leporinus desmotes is assessed by the IUCN Red List as Least Concern, with FishBase citing that assessment as dated June 2020. The species' range across the Rupununi basin of Guyana, Suriname and Brazil is not flagged with specific conservation pressures in the cited sources; as with many Guiana Shield freshwater fish, it benefits from a comparatively intact watershed relative to more heavily developed South American river systems, though no source here quantifies current population trend or threat level beyond the LC status itself.