Taxonomy & naming
Psalidodon kalunga was described by Bertaco and Carvalho in 2010 as a new species from the upper Rio Doce basin in the state of Minas Gerais, Brazil. The Rio Doce drainage was, at the time of its description, considered ichthyofaunistically poorly known in its upper reaches, making the discovery of an additional endemic characid unsurprising. The species was originally placed in Astyanax, the sprawling and taxonomically contentious genus that has long served as a catch-all for mid-sized characins across the Neotropics.
Subsequent molecular and morphological work has prompted proposals to reorganise the Astyanax complex, and the species has been referred to as Psalidodon kalunga in some of the more recent literature — reflecting revisions to the broader genus. Catalog of Fishes should be consulted for the current accepted name; both names appear in the literature and in database entries. The authority, Bertaco and Carvalho 2010, is unambiguous in either case.
This fish was long listed as Astyanax kalunga; Eschmeyer's Catalog of Fishes places the species in Psalidodon, and the current combination Psalidodon kalunga is followed here.
Morphology
Psalidodon kalunga is a small characid, reaching approximately 2.1 in standard length. The body plan is typical of the Astyanax group: moderately compressed, with a relatively high body profile, a terminal mouth, and the characteristic adipose fin behind the dorsal. Coloration in preserved specimens follows the genus norm — a silvery body with a dark lateral stripe or blotch near the caudal peduncle — though precise in-life coloration details are not well documented in the available literature.
As a small member of the genus it likely resembles the many other Astyanax species found in the upper Rio Doce system, and distinguishing it from congeners in the field requires careful attention to meristic and morphometric characters. Detailed morphological data are available in the original description by Bertaco and Carvalho.
Habitat
The species is endemic to the upper Rio Doce basin in Minas Gerais, Brazil, where it occupies the shallow margins of semilentic river stretches — areas with slow or near-still water adjacent to main channels. The habitat is characterised by clear water reaching depths of up to about 4 ft, channels 5–33 ft wide, and substrates of sand and accumulated leaf litter. This type of marginal, sheltered microhabitat is typical of many small characids in the upper Doce system.
The upper Rio Doce region supports a distinct ichthyofauna with multiple endemic species. Psalidodon kalunga's restricted distribution within this already-circumscribed basin marks it as a highly endemic fish, dependent on the integrity of a particular stretch of river habitat.
Feeding
No detailed dietary study specific to Psalidodon kalunga has been published in the sources available. As a member of the Astyanax complex it is almost certainly an opportunistic omnivore, consistent with the feeding ecology of the broader genus: small invertebrates (insect larvae, micro-crustaceans), fallen terrestrial insects, and plant material or algae are the typical dietary components for similar-sized species in comparable habitats.
In the aquarium, congeners of similar size accept good-quality flake and small pellets, as well as live and frozen foods such as Daphnia, micro-worms, and newly hatched brine shrimp. A varied diet is advisable to maintain condition, but specific husbandry data for this species are sparse.
Mating
No specific information on the mating behaviour of Psalidodon kalunga is available in the literature reviewed. Based on the reproductive biology documented across the Astyanax genus, the species is expected to be an egg-scattering open spawner with no pair bond and no parental involvement. Males likely pursue females during spawning events, with eggs broadcast freely into the water column or deposited among fine-leaved vegetation.
Spawning in Astyanax species is generally triggered by environmental cues such as rising water temperature, increased photoperiod, or simulated rainfall, consistent with the seasonal flood pulse of South American river systems. Until a dedicated study is conducted, these inferences from congeners remain the best available guide.
Breeding
Breeding of Psalidodon kalunga in captivity has not been documented in the accessible literature, and the species is not established in the ornamental trade. By analogy with well-studied Astyanax species, breeding would be expected to follow the classic egg-scattering pattern: sexually active fish scatter small, non-adhesive to slightly adhesive eggs among fine-leaved plants or substrate, with no parental care and a tendency for adults to consume their own eggs if not separated.
For any hobbyist working with this species, a separate breeding tank with dense planting or spawning mops, a slight temperature increase, and removal of adults after spawning would be the standard approach applied to Astyanax. Fry would initially require microscopic first foods before progressing to finely ground flake and newly hatched brine shrimp.
In the aquarium
Psalidodon kalunga is not an established aquarium fish and is essentially unknown in the ornamental trade. Its small size — around 2.1 in standard length — and the typical Astyanax temperament (active, shoaling, and peaceful towards similarly sized tankmates) suggest it would be manageable in a modest-sized planted aquarium if it were to become available, but no captive-husbandry literature exists for the species specifically.
Water conditions reflecting the upper Rio Doce basin — warm tropical temperatures, clear water, and a neutral to slightly acidic or neutral pH — would be appropriate starting parameters. Any aquarist acquiring the species would be working in essentially uncharted territory and should document their observations for the benefit of the broader community.
Conservation
Psalidodon kalunga is assessed as Least Concern (LC) on the IUCN Red List, based on an assessment dated 2018. At the time of assessment, no major range-wide threats were identified sufficient to place it in a threatened category. However, its endemism to the upper Rio Doce basin is a significant vulnerability given the catastrophic Mariana dam disaster of 2015, in which the tailings breach at the Samarco mine sent a toxic plume down the length of the Rio Doce — an event that caused widespread mortality in the river's endemic fish fauna.
Whether and to what degree Psalidodon kalunga was affected by that disaster, and how the IUCN status would be assessed were a post-disaster evaluation conducted, is not clear from the current literature. The species' dependence on a single river basin with documented environmental pressures warrants continued monitoring, even if its formal status remains Least Concern.