The genus was established by Albert C. L. G. Günther in 1868 for his new species Hypoptopoma thoracatum, on the basis of the peculiar, depressed, spatulate formation of the head with the eyes on the lateral edges of the head.
Species
There are currently 15 recognized species in this genus:
Hypoptopoma species inhabit the drainage basins to the east of the Andes, except for river systems draining to the Atlantic between the mouth of the Amazon River in Brazil and the Paraná River in Argentina.
