Taxonomy & naming
Australoheros ricani was described in 2022 by Carlos Alberto Santos de Lucena, Sven O. Kullander, Michael Norén and Bárbara Calegari, in the same PLOS ONE revision of the genus ('Conjectures and refutations: species diversity and phylogeny of Australoheros from coastal rivers of southern South America') that recognised 17 valid species and named several new ones from Rio Grande do Sul, including its sister species Australoheros mboapari. The genus Australoheros holds the southern 'chanchito' cichlids, established by Oldřich Říčan and Sven Kullander in 2006 from the old genus Cichlasoma to contain the lineage around the type species Australoheros facetus; the Cichlid Room Companion files the group in tribe Therapsini of subfamily Cichlinae. The specific epithet ricani is a patronym honouring Oldřich Říčan, the Czech cichlid systematist whose work (with Kullander) founded the genus and reshaped understanding of the southern heroines. The type locality is the Rio Morcego at Espumoso, in the upper Rio Jacuí drainage of Rio Grande do Sul, at roughly 28°53′55″S 52°49′00″W; the species is reported from tributaries of the Rio Jacuí-Mirim in that upper-Jacuí region. No junior synonyms are recognised; a 2025 correction to the original paper did not affect the species' validity.
Morphology
Australoheros ricani has the deep, laterally compressed, blunt-snouted body of a typical chanchito, with the genus's characteristic series of dark vertical bars running down the flanks. Lucena and colleagues distinguished it from the closely similar congeners of the southern-Brazilian drainages — its sister Australoheros mboapari among them — using the fine details that separate these otherwise look-alike species: the number, inclination and relative widths of the trunk bars, proportional measurements of the body and fin spines, and meristic counts of fins, scales and vertebrae, supported by molecular data. In life, Australoheros of this group are generally olive to brownish on the flanks over a paler belly, with the dark bars and a midlateral blotch intensifying during display and breeding and often some iridescent spangling on the body and unpaired fins. Because the species was described only recently and is not kept in aquaria, published notes on its live coloration and on sexual dimorphism are confined to the type material.
Habitat
The species is endemic to the upper Rio Jacuí drainage in north-central Rio Grande do Sul — the Jacuí being the principal river feeding the great Laguna dos Patos of coastal southern Brazil. The type locality is the Rio Morcego at the municipality of Espumoso, and the species occurs in tributaries of the Rio Jacuí-Mirim in that headwater region. This is subtropical upland river country on the southern Brazilian shield: clear, cool, seasonally variable streams flowing over rocky beds, in a climate distinctly cooler than the tropical lowlands most cichlids inhabit. FishBase carries no measured temperature, pH or depth figures for ricani; its environment is characterised here from the geography and climate of its upper-Jacuí range rather than from species-specific water data.
Feeding
No dietary study has been published for Australoheros ricani. As a chanchito cichlid it is, by the consistent ecology of the genus, an opportunistic benthic omnivore — taking aquatic insect larvae and other small invertebrates, detritus, algae and plant matter foraged from the stream bottom and from rocks and submerged wood. Its deep body and short, robust jaws fit a fish that works over and among structure rather than one built for open-water hunting. With no gut-content data available, this is an inference from well-studied relatives such as Australoheros facetus rather than a direct observation for ricani.
Mating
Mating behaviour has not been described for ricani specifically, but it can be stated from the uniform biology of the genus. Australoheros are monogamous, pair-bonding biparental substrate spawners: a male and female form a lasting pair, clean a spawning site on a firm surface, and defend a shared territory around it, courting with lateral displays, fin-spreading and intensified barring. As in the southern congener Australoheros facetus, the pair turns markedly territorial and aggressive toward intruders during breeding, with the female commonly taking on a darker, higher-contrast breeding dress. In its cool, seasonal highland range, breeding readiness would be expected to track the warmer part of the year.
Breeding
There is no published account of breeding in Australoheros ricani, and clutch size, egg number and developmental timing are unrecorded. By the consistent biology of the genus it is an open, biparental substrate spawner: adhesive eggs are laid on a cleaned hard surface and guarded by both parents — the female fanning and tending the clutch, the male patrolling the perimeter. After hatching the larvae are moved to substrate pits, and once free-swimming the fry are herded and defended as a school by both adults. This extended biparental care is the reliable template across captive-bred Australoheros, most familiarly the long-kept Australoheros facetus ('chanchito'); ricani is presumed to follow it, though this remains an extrapolation rather than a recorded observation.
In the aquarium
Australoheros ricani has no presence in the aquarium hobby. Described only in 2022 from a headwater drainage in Rio Grande do Sul, it has never been a trade fish, carries no commercial name, and is known essentially from the museum material of its original description. There is no species-specific keeping, water-chemistry or breeding information for it.
What little husbandry guidance can be offered is borrowed from the genus, and should be read as such. Australoheros are among the hardier and more cool-tolerant New World cichlids — relevant here, since ricani is a subtropical highland fish from cool, clear streams and would want lower temperatures than tropical species, in well-oxygenated water over a rocky and sandy bottom with cover and territory structure. As a medium chanchito, a breeding pair would need defended space, a reasonable tank footprint, robust filtration and a varied omnivore diet of small frozen and live invertebrates, quality sinking foods and some plant matter. The honest framing is that this is a newly described, range-restricted endemic with no aquarium history — a fish of scientific rather than hobby interest for now.
Conservation
Australoheros ricani has not been evaluated by the IUCN and carries no Red List status, reflecting how recently it was described. That lack of assessment is the key point: this is a narrow-range endemic of a single upper-Jacuí drainage, precisely the sort of restricted-distribution southern-Brazilian fish most exposed to localised habitat change. The upper Jacuí and its highland tributaries face the region's familiar pressures — agriculture and land-use change, water abstraction and damming, and pollution — which can threaten small-range endemics ahead of any formal conservation review. The original describers (Lucena et al. 2022) note the species had not been evaluated by the IUCN at the time of description. No CITES listing applies, and the species is of no fishery or commercial interest.