Taxonomy & naming
Australoheros ipatinguensis was described by the Brazilian ichthyologists Felipe P. Ottoni and Wilson J. E. M. Costa in 2008, in a taxonomic revision of the genus published in Vertebrate Zoology (volume 58) that erected nine new species from southeastern Brazil at a single stroke. The genus Australoheros itself had been raised only two years earlier, by Oldřich Říčan and Sven O. Kullander (2006), to hold the southern 'chanchito' cichlids long buried in the catch-all genus Cichlasoma — specifically the assemblage clustered around the type species Australoheros facetus. These are the heroine cichlids of subtropical and temperate South America, ranging from the Río de la Plata system north through the Paraná and Uruguay drainages and into the isolated coastal basins of eastern Brazil. Within that radiation, ipatinguensis belongs to the southeastern-Brazilian coastal group; the Cichlid Room Companion files the genus in tribe Therapsini of the subfamily Cichlinae. The species name commemorates the city of Ipatinga in Minas Gerais, near where the type series was thought to have been collected. That attribution later proved imprecise: in 2020 Ottoni, Axel Katz and Pedro Bragança published a formal correction of the type locality (Ichthyological Exploration of Freshwaters 30), having tracked down Wilson Costa's original 1990 field notebook. The holotype (UFRJ 7553) had in fact been taken not at Ipatinga but at Córrego Braúna, a tributary of the Rio Santo Antônio in the municipality of Belo Oriente — the name 'Braúna,' a common Brazilian tree, having been mistakenly tied to Ipatinga. No junior synonyms are recognised.
Morphology
This is a small cichlid: the type series tops out at about 2 in standard length (FishBase), making ipatinguensis one of the smallest Australoheros and a true dwarf alongside the larger southern members of the genus, which can exceed 6 in. The body is the deep, laterally compressed, short-snouted form typical of the chanchitos, with a body depth running 47–51% of standard length. Fin counts from the original description give 15 dorsal-fin spines with 10–11 soft rays, 7 anal-fin spines with 9 soft rays, 25–26 scales in the longitudinal row, and 26 vertebrae. Ottoni and Costa separated it from its congeners on a suite of fine osteological and meristic characters rather than on obvious external markings: a relatively non-robust snout, a narrow ectopterygoid, the absence of a depression on the head and of a dark mark on the side of the head, 24–25 proximal radials at the dorsal-fin base, 13 at the anal-fin base, and the two arms of the seventh vertical trunk-bar being of equal width. Like other Australoheros it carries a series of dark vertical bars down the flanks and a dark midlateral blotch; precise live coloration is poorly documented, as the species is essentially unknown in aquaria and the description rests on preserved material.
Habitat
Australoheros ipatinguensis is endemic to the Rio Doce basin in eastern Minas Gerais, Brazil — a medium-sized Atlantic-slope river system draining the eastern Brazilian shield to the sea in Espírito Santo. The corrected type locality is Córrego Braúna, a small tributary of the Rio Santo Antônio (itself a major Doce affluent), in the municipality of Belo Oriente, sampled along a secondary road off the MG-232 highway between Santana do Paraíso and Belo Oriente. The species is a freshwater, benthopelagic fish of warm tropical lowland streams. Beyond the type material very little has been published on its precise distribution within the basin or on the physical character of the waters it inhabits, and FishBase carries no measured temperature, pH or depth data for it. The Rio Doce drains one of the most heavily industrialised and historically deforested basins in southeastern Brazil — the same system devastated by the 2015 Mariana (Fundão) tailings-dam collapse — so the natural habitats of its small endemic fishes are under sustained pressure.
Feeding
No direct dietary study has been published for Australoheros ipatinguensis. As a small heroine cichlid it is, on the evidence of its better-known relatives, an opportunistic benthic omnivore: Australoheros species generally take aquatic insect larvae and other small invertebrates, detritus, algae and plant material picked from the substrate and from submerged surfaces. FishBase places it at an estimated trophic level of about 3.1, derived from its body size and the trophic ecology of close relatives rather than from gut-content data — consistent with a small invertivore-leaning omnivore. Its short, deep body and small mouth fit a fish that forages over the stream bottom and among structure rather than one that pursues prey in open water.
Mating
Reproductive behaviour has not been documented for ipatinguensis specifically, but the genus is uniform enough that the pattern can be stated with confidence. Australoheros, like the wider 'chanchito' lineage, are monogamous, biparental substrate spawners that form lasting pair bonds and defend a shared territory. Pairs select and clean a spawning surface — a flat stone, a sunken log or a cleared patch of substrate — and court with the usual cichlid repertoire of lateral displays, fin-spreading and intensified barring, the female typically taking on a darker, higher-contrast breeding dress. In the well-studied southern congener Australoheros facetus, pairs become markedly territorial and aggressive around the nest during breeding; the same is expected here, scaled to a much smaller fish.
Breeding
There is no published account of breeding in Australoheros ipatinguensis in the wild or in captivity, and clutch size, egg number and developmental timing are unrecorded for the species. By the consistent biology of the genus it is an open, biparental substrate spawner: adhesive eggs are laid in rows on a cleaned hard surface and guarded by both parents, with the female concentrating on fanning and tending the clutch and the male patrolling the territory. After hatching, the larvae are moved to pits in the substrate and, once free-swimming, the fry are herded and defended as a school by both adults. In its captive-bred relatives (most familiarly Australoheros facetus, long kept under the name 'chanchito') this extended biparental care is reliable and the fish are productive spawners; ipatinguensis is presumed to follow the same template, but this remains an inference rather than an observation.
In the aquarium
Australoheros ipatinguensis is essentially absent from the aquarium trade. It has no established presence in the hobby, no trade name of its own, and is known almost entirely from preserved museum material; what little is kept under the broad label 'Australoheros' in aquaria is overwhelmingly Australoheros facetus and a handful of the larger southern species, not this Rio Doce endemic. No species-specific maintenance, water-chemistry or breeding guidance exists for it.
Any keeping advice can therefore only be extrapolated from the genus, and should be read with that caveat. Australoheros as a group are hardy, adaptable chanchitos that do well in cooler, well-oxygenated water than most tropical cichlids tolerate, in tanks with a sandy or fine-gravel bottom, scattered rockwork and wood for cover and territory boundaries, and robust filtration. Being a genuinely small fish — under 2.5 in — ipatinguensis would not need the large footprint its bigger relatives demand, but as a substrate-spawning cichlid a single pair would still want its own defended space and quiet, similarly small tankmates. A varied omnivore diet of small frozen and live invertebrates, quality sinking pellets and some plant matter would suit it. The honest summary is that this is a scientifically described but horticulturally unknown fish: a candidate for the specialist who happened to collect it at the source, not a tank fish with a track record.
Conservation
The IUCN Red List assesses Australoheros ipatinguensis as Least Concern, in an assessment dated 7 November 2018. The listing reflects the absence of evidence of decline rather than a well-monitored, secure population: this is a narrow-range endemic known from a single river basin, and small Atlantic-slope endemics of southeastern Brazil are exactly the fishes most exposed to habitat loss. The Rio Doce basin in particular has suffered intense historical deforestation, agricultural and urban pollution and industrial pressure, and was the scene of the catastrophic 2015 Fundão tailings-dam failure near Mariana, which sent mine waste down the length of the Doce to the Atlantic. None of these pressures has been documented as a population-level threat to ipatinguensis specifically — in part because the species is so little studied — but its restricted distribution within a heavily impacted basin is the relevant context for its status. It carries no CITES listing and is of no fishery or commercial interest.