Taxonomy & naming
Leporellus cartledgei was described by the American ichthyologist Henry Weed Fowler in 1941, with a type locality at Penedo on the Rio São Francisco in Pernambuco, Brazil. It sits in the genus Leporellus, a small headstander lineage of four described species within the family Anostomidae (order Characiformes), the same broad headstander family that contains the much larger and more familiar genera Leporinus and Anostomus.
The taxonomic status of L. cartledgei is not fully settled: some authorities treat it as possibly a junior synonym of Leporellus pictus (Kner, 1858), while others continue to recognise it as a valid, distinct species. This account follows the traditional treatment of L. cartledgei as valid pending a definitive taxonomic revision, consistent with the Catalog of Fishes as the standing authority on valid names. As with many Leporellus, there is no confirmed common or trade name in circulation for this species specifically.
Morphology
Like other members of its genus, Leporellus cartledgei has the elongated, torpedo-shaped body typical of headstanders — built for holding position against current while grazing rather than for open-water speed. Detailed morphometric data specific to this species is not available in accessible literature, so this account does not attempt to describe fin counts, exact body proportions or colour pattern beyond what is documented for the genus as a whole.
Size is likewise not confirmed for L. cartledgei directly. The better-studied congener Leporellus vittatus reaches roughly 10 in, and L. cartledgei is presumed to fall in a broadly similar range of around 8–10 in, but this figure is an estimate carried over from a relative, not a measurement of the species itself, and should be treated as unconfirmed.
Habitat
Leporellus cartledgei is known from the Rio São Francisco basin in Brazil, with the genus more broadly distributed across the São Francisco and Paraná-Paraguay river systems of South America. Within these systems it is a freshwater, riverine species, consistent with the headstander habit of grazing rock, wood and other submerged surfaces in flowing water.
Water conditions reported for the genus are soft to neutral, with a pH around 6.0–6.5, hardness up to about 12 dH, and tropical temperatures in the range of roughly 72–77 °F. Leporellus generally favour well-lit water with good current, which supports the algal and biofilm growth the fish grazes on; this account uses these genus-level figures because no species-specific water chemistry data was found for L. cartledgei.
Feeding
Leporellus cartledgei is a grazer, feeding in the characteristic head-down, oblique posture of headstanders as it works over algae, biofilm and aufwuchs on wood, rock and other submerged surfaces. Diet across the genus is predominantly herbivorous, supplemented opportunistically with small invertebrates and plankton.
In the aquarium, congeners of this species are maintained on a largely vegetable diet — blanched lettuce, peas, zucchini and algae wafers — with occasional small live or frozen protein such as worms. No feeding data specific to L. cartledgei was found, so this account follows the documented genus-level pattern rather than assuming identical behaviour has been confirmed for this species.
Mating
No courtship or spawning behaviour specific to Leporellus cartledgei has been documented in accessible sources. Within the genus, individuals are reported to establish a loose social hierarchy when kept in groups, but there is no confirmed account of pairing, courtship display or spawning triggers for this species or its close relatives.
External sexual dimorphism is not documented for L. cartledgei, and this account does not speculate on how the sexes might be distinguished.
Breeding
Leporellus cartledgei has, as far as available sources indicate, never been documented breeding in the aquarium, and captive breeding within the genus as a whole is rare. Where breeding has been reported in related headstanders such as some Leporinus and Anostomus species, the mode is egg-scattering with no parental care, and this is the most plausible pattern for Leporellus by extension — but it has not been confirmed for L. cartledgei specifically, and no clutch size, incubation period or fry-rearing account exists for this species.
Given the near-total absence of breeding data, prospective keepers should not expect to spawn this species in a home aquarium, and any claims of successful captive breeding should be treated with caution pending documentation.
In the aquarium
Leporellus cartledgei is essentially unknown in the aquarium trade, with no established care profile or supply chain specific to the species. Care recommendations here are therefore extrapolated cautiously from the genus: a spacious, well-filtered aquarium with strong water movement and good lighting to support algal grazing, soft-to-neutral water around pH 6.0–6.5 and roughly 72–77 °F, and driftwood or rock surfaces for the fish to graze.
As with other headstanders and many Anostomidae, keepers should be alert to the possibility of nippy or territorial behaviour as fish mature, particularly toward slower or long-finned tankmates, even though this has not been documented for L. cartledgei itself. Because reliable size, temperament and husbandry data for this exact species is so sparse, anyone acquiring it should treat published Leporellus genus-level guidance as a starting point rather than a guarantee, and should size the tank to the larger end of the estimated 8–10 in adult range.
Conservation
Leporellus cartledgei has not been evaluated by the IUCN Red List, so its conservation status is formally Not Evaluated. This is consistent with its status as a poorly studied, single-basin characin — no population trend, threat assessment or abundance data was found in accessible sources.
Its native range in the Rio São Francisco basin is subject to the general pressures facing Brazilian freshwater systems, including damming, water abstraction and habitat modification, but no source specifically ties these pressures to L. cartledgei's population status. In the absence of a formal assessment, its conservation standing should be considered unknown rather than assumed safe.