Taxonomy & naming
Psalidodon uberaba was described by Serra and Langeani in 2015 from the headwaters of the Rio Uberaba, a tributary of the upper Rio Grande basin in Minas Gerais, Brazil. The species has since been moved between several genus-level arrangements that reflect ongoing disagreement within the broader Astyanax complex. The IUCN Red List's 2020 assessment treats the fish as Hasemania uberaba, while a 2024 phylogenomic revision of Characidae by Melo and colleagues — analysing genome-wide markers across the family — recovered the species within Psalidodon, a genus resurrected to accommodate many former Astyanax from South America's central river basins. Psalidodon is diagnosed in part by the absence of an adipose fin, an interrupted lateral line, and a scaleless caudal fin.
Eschmeyer's Catalog of Fishes remains the governing authority for valid names used on this site; the name presented here reflects the original description. Regardless of the genus assignment, the species-level identity is stable and the type locality unambiguous: the headwater marshes of the Rio Uberaba, where the species appears to be confined.
This fish was long listed as Astyanax uberaba; Eschmeyer's Catalog of Fishes places the species in Psalidodon, and the current combination Psalidodon uberaba is followed here.
Morphology
Psalidodon uberaba is a small, slender-bodied tetra reaching approximately 2.8 in standard length, placing it in the upper size range for the genus in this basin. Like related small characids, it has a moderately compressed body, a forked tail, and the family's characteristic adipose fin — though the phylogenomic data suggest the adipose may be reduced or absent in some taxonomic interpretations of the group it has been placed in.
Formal meristic and morphometric data are not reproduced in the cache for this species, and detailed morphological description is absent from the secondary sources consulted. The original Serra and Langeani (2015) description provides the authoritative account. In general body plan the species is consistent with the Astyanax alliance: silvery-flanked, with a relatively large eye, terminal mouth, and the short, deep dorsal fin typical of the group.
Habitat
The species is known only from the headwaters of the Rio Uberaba in the upper Rio Grande basin, itself part of the upper Paraná drainage. This is Cerrado country — Brazil's tropical savanna — where headwater streams form through seasonally flooded marshlands dominated by Cyperaceae (sedges) and Poaceae (grasses), with abundant filamentous algae growing over muddy substrates. The water is characteristically crystalline and softly illuminated through low emergent vegetation rather than closed canopy.
Water chemistry data from FishBase records a temperature of around 77 °F and a pH of approximately 6.5, consistent with the moderately soft, slightly acidic to neutral conditions typical of Cerrado headwaters that have not been strongly influenced by calcareous geology. The combination of clear water, fine silty bottom, and dense marginal vegetation is a defining feature of the microhabitat, and likely shapes both the species' feeding ecology and its reproductive behaviour.
Feeding
Dietary analysis from FishBase records that Psalidodon uberaba feeds on angiosperms (flowering plant material), larvae of Chironomidae (non-biting midges, Diptera), and Trichoptera (caddisfly larvae). This combination — plant matter plus aquatic insect larvae — is typical of small omnivorous characids that forage across the interface of submerged vegetation and soft-bottom habitats, picking up invertebrates dislodged from plant surfaces alongside ingested organic and plant fragments.
In the aquarium, comparable Astyanax alliance tetras accept a wide range of prepared and live foods. A diet of quality small-granule or crushed flake food supplemented with frozen chironomid larvae (bloodworm), Daphnia, and brine shrimp would replicate the wild profile reasonably well. The plant-matter component of the diet suggests that some vegetable content — spirulina flake or blanched plant material — would be beneficial.
Mating
No specific mating behaviour has been documented for Psalidodon uberaba in the literature, and the original description does not record observations from the wild. The species is expected to follow the egg-scattering reproductive strategy universal in the Astyanax alliance: males court females in open water or among fine-leaved vegetation, releasing sperm as the female deposits small adhesive eggs among plants or over the substrate.
In species of this group, courtship is typically brief and non-territorial, with males pursuing females actively. Display behaviour in small Astyanax is modest compared to cichlids — colour intensification and fin-spreading are the primary signals. Because no parental bond forms and eggs are scattered, multiple males may participate in a single spawning event in the wild.
Breeding
Breeding has not been documented in captivity for Psalidodon uberaba specifically, and the cache notes breeding as unknown or undocumented. Based on closely related small characids, the expected mode is open egg-scattering with adhesive eggs deposited among fine-leaved aquatic plants or over soft substrate, with no parental care from either sex. Adults will consume their own eggs if given the opportunity.
A breeder attempting this species would follow standard practice for small Astyanax: condition adults separately on live and frozen foods, transfer a group of well-fed fish to a bare-bottom or moss-filled spawning tank at slightly elevated temperature, and remove the adults once spawning is observed. Eggs of related species hatch within two to three days at tropical temperatures, with fry becoming free-swimming shortly after. First foods would be infusoria or commercial liquid fry food, followed by newly hatched brine shrimp.
In the aquarium
Psalidodon uberaba is not established in the ornamental trade and is rarely if ever encountered in hobby channels outside of specialist collections in Brazil. Its restricted range, modest size, and silvery appearance mean it has attracted little commercial interest compared with brightly coloured congeners. Aquarists working with small Brazilian tetras who obtain this species should house it in a well-planted tank replicating its Cerrado headwater habitat: soft, slightly acidic to neutral water around 75–79 °F, a dark or sandy substrate, and dense planting with fine-leaved species at the margins.
As a small schooling characid it should be kept in groups of six or more to express natural behaviour and reduce stress. The species' headwater origin suggests it would prefer low to moderate flow, clean water, and stable conditions rather than fast-moving or heavily aerated tanks. Peaceful tankmates of similar size — other small South American tetras, small corydoras, and dwarf cichlids — would be compatible. Data on temperament, hardiness, and longevity in captivity are absent from the sources consulted.
Conservation
Psalidodon uberaba is assessed as Least Concern (LC) on the IUCN Red List, with the most recent assessment published in 2020 under the name Hasemania uberaba. The LC designation reflects that, while the species is known from a restricted area, no evidence of rapid decline, critically small population, or severe habitat collapse was identified at the time of assessment.
Nonetheless, the species' entire known range falls within the Rio Uberaba headwaters — a small Cerrado watershed subject to the pressures typical of this biome: agricultural conversion, stream channelisation, sedimentation, and seasonal water extraction. The Cerrado is one of the world's most threatened biodiversity hotspots, with a large proportion of its original extent already converted to agriculture. A species known only from the headwaters of a single river in this landscape warrants monitoring, and future reassessments should account for any documented changes in habitat extent or water quality across its small range.