Taxonomy & naming
Leporinus melanopleurodes was described in 2013 by José Birindelli, Heraldo Britski and José Carlos Garavello, in the same paper (published in Neotropical Ichthyology) that also described a second new species and redescribed the related Leporinus melanopleura Günther. It belongs to the family Anostomidae — the headstanders — within the order Characiformes, and to the large genus Leporinus, which the Catalog of Fishes (Eschmeyer, California Academy of Sciences) recognises as holding dozens of valid species distributed across South America.
The species epithet "melanopleurodes" signals its close resemblance to L. melanopleura, the species from which it was split; the authors distinguished it on the basis of subtle morphological differences (fin-ray and vertebral counts, colour pattern) found in specimens from the small, isolated Bahia coastal river systems rather than the larger interior basins where L. melanopleura itself occurs. As a species described only in 2013 from a narrow range, it has not accumulated the trade or hobby history of better-known Leporinus such as L. fasciatus, and it does not appear to have an established common name.
Morphology
Leporinus melanopleurodes is a small, elongate, torpedo-shaped headstander, with the largest specimen examined in the original description measuring 5 in standard length (roughly 5 in) — modest for the genus, many members of which exceed 8–12 in. FishBase and the original description record 12 dorsal soft rays, 10 anal soft rays and 37–38 vertebrae, counts used alongside colour pattern to separate it from the closely similar L. melanopleura.
As in other Leporinus, the body is compressed and streamlined for holding position in current, with a small, ventrally positioned mouth adapted for scraping algae and biofilm from hard surfaces — the anatomical basis for the genus's distinctive head-down grazing posture. Detailed live colouration has not been widely documented for this species beyond the preserved-specimen descriptions in the taxonomic literature; data is sparse on how colour and pattern present in life.
Habitat
The species is known only from the Rio das Almas and Rio Jiquiriçá, two short, independent coastal river drainages in Bahia, northeastern Brazil, that flow directly to the Atlantic rather than draining into the Amazon, Paraguay-Paraná or São Francisco systems. The type locality lies in the Rio das Almas near Nilo Peçanha, Bahia (13°36'27.8"S, 39°8'38.8"W).
Within these rivers it occupies fast-flowing rapids over clear water and a rocky bottom densely covered in Podostemaceae — river-weeds that anchor to rock in high-current stretches and that, along with the rock surfaces themselves, supply the algae and biofilm this species grazes. That combination of swift current, clear water and rock-and-riverweed substrate is the core physical picture the original description gives; specific water-chemistry data (pH, hardness, temperature) has not been published for this species, though nearby Bahia coastal rivers are generally warm, clear lowland systems.
Feeding
Leporinus melanopleurodes is an aufwuchs grazer, feeding on algae and biofilm scraped from rock surfaces and the Podostemaceae river-weeds of its rapids habitat, consistent with its small, ventral, scraping mouth. No stomach-content study specific to this species has been published, but this feeding mode is well established for the genus generally, and several Leporinus and related headstanders also take soft aquatic plants and some small invertebrates opportunistically.
In the aquarium, genus-level care guidance (drawn from better-documented relatives such as L. fasciatus and L. nijsseni) points to a diet built around vegetable matter — algae wafers, blanched vegetables, spirulina-based foods — supplemented with some protein such as small live or frozen invertebrates. Soft-leaved aquarium plants should be expected to take grazing damage from a headstander kept long-term.
Mating
No courtship or spawning behaviour has been documented for Leporinus melanopleurodes specifically. Data is sparse even at the genus level: Leporinus and other headstanders are not known for elaborate pair-bonding rituals, and hobby accounts of related species describe little more than a period of chasing and increased activity ahead of scattering eggs, with no reliable external sexual dimorphism reported for most species in the genus.
Breeding
Leporinus melanopleurodes has no published aquarium or captive breeding record. Headstanders as a group are egg-scatterers that broadcast adhesive eggs over vegetation or fine substrate with no parental care, and this is rarely achieved in home aquaria; a handful of Leporinus and Anostomus species have been spawned by dedicated hobbyists, and some larger Leporinus are farmed commercially, but nothing specific has been reported for this narrow-range Bahia endemic. Anyone attempting to breed it would be working from the genus-level pattern rather than any species-specific account.
In the aquarium
There is essentially no published aquarium-keeping record for this species, so what follows is drawn from its close relatives and should be treated as a starting point, not a settled care sheet. At a maximum recorded size of roughly 5 in SL it stays smaller than many popular Leporinus, but the genus has a well-earned reputation for territoriality and fin-nipping as fish mature, and this species should not be assumed gentle by default. A tank built around strong water movement, a hard rocky substrate and algae-covered surfaces to graze would mirror its rapids habitat; soft-leaved plants are likely to be grazed or shredded.
Given the total absence of species-specific husbandry data, a prospective keeper should default to the general Leporinus playbook: generous swimming space, robust filtration and current, a varied diet weighted toward vegetable matter, and caution about tankmates that could be nipped once the fish matures and turns territorial. This is not a species currently established in the aquarium trade.
Conservation
Leporinus melanopleurodes has not been formally assessed by the IUCN Red List and is classified here as Not Evaluated. It is known only from two small, independent coastal river drainages in Bahia, Brazil — a genuinely narrow range for any fish species — which in itself is a conservation-relevant fact even in the absence of a formal assessment: single-river and two-river endemics are inherently vulnerable to habitat degradation, damming or pollution affecting either system. No population trend or threat data has been published for this species specifically, and it does not appear to be part of the aquarium trade, so collection pressure is not a documented concern; habitat integrity in the Rio das Almas and Rio Jiquiriçá is the more plausible long-term watch item.