Piranhas & Pacus · Hemiodus & minor characins

Cyphocharax aninha

Wosiacki & Miranda, 2014

IUCNLEAST CONCERN · 2020
CARESNOT LISTED
Scientific size1.5 in3.9 cm standard length
Temperature73–81 °F23–27 °C
Depthnot recorded
DietNot directly studied for this species; family Curimatidae are characteristic detritus- and biofilm-grazers, and this species' small size is consistent with that niche
BreedingNot documented for this species; data sparse. A related species, Cyphocharax multilineatus, is a substrate egg-scatterer associated with vegetation, offered here as genus-level context only
Sexual dimorphismMinimalNo external sexual dimorphism documented; data sparse
PhotographsSee photosGoogle Images →

Cyphocharax aninha is a tiny, unassuming characin from the family Curimatidae — the curimatas, a group of quiet, detritus-grazing shoalers that live in the shadow of their flashier Serrasalmidae cousins. Described only in 2014 from the Rio Mopeco, a small left-bank tributary of the Rio Parú in Pará, Brazil, it is a genuinely small fish: FishBase records a maximum size of just 1.5 in standard length, smaller than many aquarium tetras. It is not a piranha, not a pacu, and not a fish anyone keeps for spectacle — it is exactly the kind of narrow-range, scientifically documented but hobby-obscure minor characin that fills out the true diversity of Neotropical rivers. Data on its biology beyond the original description and FishBase are sparse, and this account says so plainly rather than filling gaps with guesswork.

What's in the name

Cyphocharax aninhasy-foh-KAR-ax ah-NEE-nyah

Cyphocharax
  • kyphosGreekhunched, bent, curved — referring to the arched or humped body profile typical of the genus
  • charaxGreeka pointed stake or a type of fish — a common characin-genus suffix referring to the family's generally spindle-shaped body
aninha
  • aninhaLatinized eponym or vernacularthe specific epithet as coined by Wosiacki & Miranda in 2014; the precise dedication or derivation is not documented in the sources available here

Taxonomy & naming

Cyphocharax aninha was described by Wosiacki & Miranda in 2014, one of many curimatid species formally recognised only in the last two decades as taxonomists worked through the Amazon basin's poorly resolved detritivore fauna. It belongs to the genus Cyphocharax within the family Curimatidae, part of the broader superfamily that also contains Prochilodus and the true Curimata — all small-to-medium characins built around a toothless, sediment- and biofilm-grazing lifestyle rather than the predatory or frugivorous habits of piranhas and pacus in the neighbouring family Serrasalmidae.

The type locality is the Rio Mopeco, a left-bank tributary of the Rio Parú in the state of Pará, Brazil, placing the species firmly within the Amazon basin. As with many recently described curimatids, C. aninha is known primarily from its original description and subsequent listing in taxonomic databases; the Catalog of Fishes (Eschmeyer, California Academy of Sciences) is the governing authority for the valid combination, and nothing in the available record suggests any subsequent reclassification or synonymy for this name.

Morphology

Cyphocharax aninha is a genuinely small fish even by the standards of minor characins: FishBase lists a maximum published length of 1.5 in standard length for both male and unsexed specimens, with no larger female size on record. That places it among the smallest members of a genus that already runs small relative to its Curimatidae relatives.

Beyond the size record and its placement in a benthopelagic, freshwater, tropical lifestyle, detailed morphological description is limited in publicly available sources. Like other Cyphocharax, it can be expected to share the family's general body plan — a slim, silvery, laterally compressed shoaling fish with a small, subterminal or ventrally positioned mouth adapted for scraping detritus, algae and biofilm rather than a jaw built for seizing prey. Data on colour pattern, fin counts and other diagnostic detail specific to this species is sparse in the sources available here, and this account does not speculate beyond what is documented.

Habitat

Cyphocharax aninha is documented from the Rio Mopeco, a tributary of the Rio Parú, within the Amazon River basin in Pará, Brazil. FishBase characterises the species as benthopelagic and freshwater, tropical in distribution — consistent with a small tributary stream in the lowland Amazon rather than a large main-channel river.

Specific water chemistry data for C. aninha itself is not available in the cache. A related species in the same genus, Cyphocharax multilineatus, is documented inhabiting warm water in the range of roughly 23–27 degrees Celsius at neutral to slightly acidic pH, which is broadly consistent with typical Amazon tributary conditions, but this is offered as genus-level context rather than a confirmed reading for C. aninha itself.

Feeding

Curimatidae as a family are characteristic detritus-grazers: most species in this group, including the broader genus Cyphocharax, feed by sifting or scraping fine organic sediment, algae and biofilm from the substrate rather than hunting prey or taking large food items. No species-specific dietary study of C. aninha is available in the sources consulted here, but its family placement and its very small adult size are both consistent with this detritivorous, low-impact grazing lifestyle rather than anything predatory or opportunistic.

In a hypothetical aquarium setting, a fish built for this niche would be expected to do best on fine, sinking foods, algae-based wafers and general detrital grazing opportunities rather than large meaty items — though the species is not established in the trade and this is inference from its family, not a documented care record.

Mating

No courtship or pairing behaviour has been documented for Cyphocharax aninha in the sources available here. Data on this species is sparse to the point that even basic reproductive biology beyond family-level generalisation cannot be responsibly reported.

Breeding

Breeding biology for Cyphocharax aninha specifically is not documented in the available sources, and this account does not assign it a breeding mode by inference alone. Within the wider genus, a related species, Cyphocharax multilineatus, has been reported as a substrate egg-scatterer associated with vegetation, and Curimatidae generally are not known as a family that is frequently or deliberately bred in captivity — they are grazers of modest hobby interest rather than trade staples with an established breeding protocol. Whether C. aninha itself has ever been spawned in captivity is unrecorded here; the honest answer is that this is unknown, not that it follows a documented pattern.

In the aquarium

Cyphocharax aninha does not appear to be an established aquarium species — it is a scientifically described but hobby-obscure curimatid known from a single small Amazon tributary, and no aquarium care record was found in the sources consulted here. At a maximum recorded size of 1.5 in SL, it would in principle suit only a very small, peaceful setup among fine-substrate grazers if it were ever available, but this is speculative extrapolation from its size and family, not a documented care history, and it should not be presented to readers as an available or proven aquarium fish.

The more useful takeaway for this species is representational: not every characin in the Amazon is a piranha, a pacu or a showy tetra. The great majority of Neotropical characin diversity, including this genus, is made up of small, quiet grazing fish like C. aninha that rarely if ever enter the trade but form the base of the food web these rivers depend on.

Conservation

Cyphocharax aninha is assessed by the IUCN Red List as Least Concern, a status corroborated by FishBase. As a narrow-range species known from a single documented tributary system within the vast Amazon basin, its conservation picture is typical of many recently described, data-poor Amazonian fishes: not currently flagged as threatened, but also not the subject of extensive population monitoring. There is no indication in the available sources of a targeted fishery or aquarium trade pressure on this species, which is consistent with its status as a scientifically documented but commercially unexploited curimatid.

Sources

  1. FishBase — Cyphocharax aninha Wosiacki & Miranda, 2014
  2. IUCN Red List — search results for Cyphocharax aninha
  3. FishBase — Cyphocharax multilineatus (related species, genus-level habitat/breeding context)

Last reviewed 2026-07-09.

How to cite

Aquarist Atlas (2026). Cyphocharax aninha. Aquarist Atlas.https://www.aquaristatlas.com/piranhas/cyphocharax-aninha/

Where it has been recorded

7 georeferenced records (GBIF). Each point is a field observation or museum specimen — pan and zoom to explore where this species turns up. The coordinates come straight from GBIF and are often rounded or tied to the nearest town or river landing, so a dot can sit just beside the actual water rather than in it.

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