Taxonomy & naming
Steindachnerina notonota was described by the Brazilian ichthyologist Alípio de Miranda Ribeiro in 1937. It belongs to the genus Steindachnerina, one of several curimatid genera erected from the old, broadly defined "Curimata" grouping as the family was revised through the twentieth century, and it sits within Curimatidae, the toothless characins, in the order Characiformes alongside the hemiodontids and prochilodontids that make up the rest of this "minor characins" group.
The genus Steindachnerina honours the Austrian ichthyologist Franz Steindachner, a prolific describer of Neotropical fishes in the nineteenth century. GBIF and FishBase both list the species under its original combination, Steindachnerina notonota (Miranda Ribeiro, 1937), with no indication in the cached sources of a subsequent generic transfer, so the name used here follows the Catalog of Fishes' governing convention without alteration.
Morphology
Like other curimatids, Steindachnerina notonota is a small, elongate, laterally compressed fish with a silvery body and no true jaw teeth — the family's defining trait, and the source of the common English name "toothless characins." FishBase records a maximum published size of 4.5 in total length, making this one of the more modest-sized fish in the Piranhas & Pacus atlas rather than an outlier even among the minor characins.
Detailed morphological description beyond size and family-level traits is sparse in the cached sources. What can be said with confidence is that the body plan follows the curimatid pattern shared with its relatives: a small subterminal or inferior mouth adapted for picking at substrate and organic material rather than for grasping prey, consistent with the detritivorous feeding habit documented for the species (see Feeding, below).
Habitat
Steindachnerina notonota is native to coastal river systems of northeastern Brazil, a region of generally warm, tropical freshwater habitats. A population and feeding-ecology study from the Taperoá II reservoir in the semi-arid interior of Paraíba state documents the species living in an impounded, tropical freshwater habitat rather than a free-flowing river reach, which suggests some tolerance for the more static, seasonally stressed conditions typical of semi-arid Brazilian dams.
The cached sources do not report specific temperature or pH ranges for the species. Given its northeastern Brazilian coastal-river distribution and its documented presence in a semi-arid reservoir, warm tropical freshwater conditions can be assumed, but no numeric water-chemistry data is available to cite here — that gap is reflected honestly in the facts below rather than filled with an invented range.
Feeding
Steindachnerina notonota is a detritivore. The Taperoá II reservoir study describes its diet as centred on debris and organic matter picked from the bottom, consistent with the toothless, substrate-oriented feeding apparatus shared across Curimatidae. This places it with the quiet grazing curimatas and hemiodontids of this group rather than with the predatory or fruit-and-seed-eating characins found elsewhere in Piranhas & Pacus.
No aquarium feeding account exists in the cached sources, since the species is not established in the hobby. Based on its documented detritivorous diet in the wild, a captive diet mirroring that of other small detritus-feeding curimatids — sinking wafers, blanched vegetable matter and fine particulate foods — would be the reasonable inference, but this is not confirmed by any source specific to this species.
Mating
No courtship or spawning-behaviour account for Steindachnerina notonota appears in the cached sources. The species has not been documented in aquaculture or aquarium breeding contexts, and the available literature is limited to a population and feeding-ecology study rather than a reproductive-biology study.
Breeding
Breeding biology for this species is not documented in the cached sources, and it should not be assumed to follow any particular mode. Most Curimatidae for which reproductive behaviour has been studied are open-water or riverine egg-scatterers with no parental care, consistent with the group's general pattern among the minor characins, but this has not been specifically confirmed for Steindachnerina notonota and no source here supports assigning it that mode with confidence. It is not known to be bred in the aquarium hobby or in commercial aquaculture; data is simply sparse for this species.
In the aquarium
Steindachnerina notonota is not established in the aquarium trade. It does not appear in the cached sources as a hobby fish, and no care guide, tank-size recommendation, or aquarium water-parameter data exists for it. Any aquarist interested in the species would be working from its wild ecology alone: a modest adult size of around 4.5 in total length, a detritivorous, bottom-oriented feeding habit, and a native range of warm tropical freshwater in northeastern Brazil, including at least one semi-arid reservoir system.
Given the complete absence of husbandry data, this entry makes no specific stocking, tankmate or water-parameter recommendations — doing so would mean inventing details not supported by any source. This is one of the many minor characins in this atlas that exists almost entirely as a documented wild population rather than as a hobby fish.
Conservation
The IUCN Red List assessment for Steindachnerina notonota is Least Concern, as reported by FishBase with an assessment date of 07 November 2018; the cached sources were not able to locate a dedicated IUCN Red List species page to confirm the assessment ID directly, so the IUCN link below points to a search query rather than a specific record. A Least Concern rating is broadly consistent with a small, non-commercially-targeted detritivore occupying multiple coastal river and reservoir habitats across northeastern Brazil rather than a single threatened locality.
The species' documented presence in the Taperoá II reservoir — an artificial impoundment in semi-arid Paraíba — indicates it tolerates altered, impounded habitats, which may support population stability even as natural coastal river reaches in the region face pressure from damming and water extraction typical of Brazil's semi-arid interior. No fishery or trade pressure is documented for this species in the cached sources.