Cnesterodon pirai, the Almeida toothcarp, is a species of poeciliid that is only know from its type locality, the arroyo Almeida, an affluent of the arroyo Cuñá-Pirú, in the RÃÂo Paraná basin, Aristóbulo del Valle, Misiones in Argentina.
This species reaches a length of TL.
The species name meaning is pirá, a Guarani word for fish and the àdiminutive, referring to the small size of the fishes in this genus.