Taxonomy & naming
Curimatopsis myersi was described by the American ichthyologist Richard P. Vari in 1982. It belongs to the genus Curimatopsis, a small genus of diminutive curimatids, within the family Curimatidae — the toothless detritivorous characins sometimes grouped informally with the pacus, silver dollars and other minor characins outside the strict piranha and tetra lineages. The Catalog of Fishes (Eschmeyer, California Academy of Sciences) is the governing authority for the valid name and combination; the cache used to compile this account did not surface any subsequent taxonomic revision affecting the genus placement, so Curimatopsis myersi is treated here as currently valid.
The original description paper (Vari, 1982) is catalogued in the Biodiversity Heritage Library, but its full text was not accessible during research for this article, so the type locality is reported here only in general terms — the Paraguay River basin, in the vicinity of San Pedro — pending confirmation against the primary source.
Morphology
Curimatopsis myersi is a small characin, with FishBase recording a maximum length of 1.5 in standard length — among the smallest fish in the wider Serrasalmidae-adjacent characin assemblage covered by this atlas, and a useful reminder that this group ranges from fish this size up to the meter-plus pacus and dorados. Like other members of Curimatidae, it is toothless in the jaws; the family instead processes food using pharyngeal teeth set deep in the throat, an adaptation tied to its grazing, detritivorous feeding style rather than to seizing or crushing prey.
Detailed morphological description beyond size and the family's characteristic toothless, unusual mouth structure was not available in the sources consulted for this article; a fuller account would draw on Vari's 1982 original description.
Habitat
The species is known from the Paraguay River basin in South America, a large lowland river system shared with Brazil, Bolivia, Paraguay and Argentina. FishBase describes it as a freshwater, benthopelagic fish of tropical waters, occupying the water column just above the substrate rather than living strictly on the bottom or at the surface.
FishBase gives a temperature range of 68–79 °F for the species, cooler than the classic Amazonian norm and consistent with the more seasonal, subtropical-leaning climate of parts of the Paraguay basin. Specific pH and hardness data were not found in the sources consulted; given the general character of Paraguay basin waters, keepers and researchers should treat those parameters as unconfirmed rather than assume typical Amazonian blackwater extremes.
Feeding
Curimatopsis myersi is a member of Curimatidae, a family of toothless detritivores that feed by grazing the film of algae, biofilm and organic detritus coating submerged surfaces, supplemented opportunistically with fine organic material and zooplankton. Rather than jaw teeth, the family relies on specialised pharyngeal plate teeth to process this material, and the diet regime is generally described as omnivorous-to-detritivorous depending on the sediment and biofilm load available in a given stretch of river.
No species-specific feeding study was found for C. myersi; the account above reflects documented Curimatidae family-level ecology rather than direct observation of this species.
Mating
No courtship or mating behaviour specific to Curimatopsis myersi was found in the sources consulted for this article. Data is sparse for this small, little-studied river species, and nothing here should be inferred from better-known relatives without direct evidence.
Breeding
Breeding biology for Curimatopsis myersi is not documented in the sources available for this account, and it is not reported as bred in the aquarium hobby or in aquaculture. It would be inaccurate to assign it a specific spawning mode — such as the substrate-guarding behaviour of the true piranhas or the open-water scattering of silver dollars — without direct evidence, so this account states plainly that the species' reproductive biology is presently undocumented in the literature consulted.
In the aquarium
Curimatopsis myersi is not established in the aquarium trade. The sources consulted found a related species, C. macrolepis, exported in small numbers for the hobby and described as a very peaceful, small community fish, but C. myersi itself was not specifically documented as available or kept. Given its tiny adult size (1.5 in SL) and its family's grazing, detritivorous habits, any aquarium keeping would need to prioritise a diet of algae- and biofilm-replete surfaces or suitable prepared foods alongside fine live and frozen foods, in a peaceful community setting scaled to a genuinely small fish — but this is inference from family-level traits, not a documented care record for the species itself.
Prospective keepers should treat this species as effectively unavailable in the trade and should not expect commercial supply; anyone encountering it would be dealing with a wild-collected, likely misidentified or mixed shipment of Curimatopsis species rather than a targeted import.
Conservation
Curimatopsis myersi has not been assessed by the IUCN Red List and is classified here as Not Evaluated (NE). This is unsurprising for a small, narrowly documented river species restricted to part of the Paraguay basin, and it reflects a lack of dedicated assessment effort rather than any known population decline.
No species-specific conservation pressures were identified in the sources consulted. As with many small, obscure characins of the Paraguay system, general watch items for the wider region — water development, land-use change and sedimentation in the Paraguay/Pantanal drainage — are relevant in principle but are not documented as acting on this species specifically.