Taxonomy & naming
Nannoptopoma sternoptychum was described by Schaefer in 1996. It is placed in the subfamily Hypoptopomatinae of the family Loricariidae — the dwarf suckermouth armoured catfishes. The Catalog of Fishes (Eschmeyer, CAS) is the authority for valid names, and FishBase records the authority as Schaefer, 1996.
The genus name Nannoptopoma combines Latin nannus, meaning small, with the Greek elements ops (eye) and poma (cover, operculum), describing features of these diminutive catfishes.
Morphology
Nannoptopoma sternoptychum is very small, reaching a maximum recorded length of about 1.5 in SL. As implied by the genus name, it is a small-bodied hypoptopomatine. Detailed meristic and colour-pattern descriptions beyond the original description are not summarised in the available sources and are not reconstructed here. Sexual dimorphism has no data published for this species.
Habitat
The species occurs in South America across Ecuador, Peru and Bolivia, in the upper and central Río Amazonas and the upper Rio Madeira basin. It is a freshwater, demersal species of tropical waters. More specific habitat data — stream type, substrate, flow regime and water chemistry — is not available in the consulted sources.
Feeding
No diet has been published for Nannoptopoma sternoptychum. Hypoptopomatines are generally aufwuchs grazers that rasp algae and biofilm from submerged surfaces, but no species-specific feeding data is available and none is asserted here.
Mating
No data published. Courtship and mating behaviour are undocumented for this species in the available sources.
Breeding
No data published. Reproductive mode, clutch size, spawning site and parental care have not been recorded for Nannoptopoma sternoptychum in the consulted sources.
In the aquarium
Nannoptopoma sternoptychum is not an established aquarium species and has no documented husbandry record. Its small size and western-Amazon, tropical freshwater origin would in principle suggest general dwarf-loricariid care, but no species-specific guidance can be offered without inventing detail.
Conservation
The IUCN Red List assessed Nannoptopoma sternoptychum as Least Concern (LC) in 2020. The assessment reflects its broad distribution across the upper and central Amazon and upper Madeira basins spanning three countries, with no evidence of significant range-wide decline in the available sources.