first record from Argentina:
Astyanax stenohalinus Messner, 1962

This species was listed with a locality from Argentina as comparative material in the description of Astyanax chico.

type locality:
Uruguay, Cerro Largo, Río Negro, Paso Mazangano

distribution in Argentina:
Buenos Aires province, Río de la Plata basin, Punta Indio, unnamed stream (AI 132)

published in:
Casciotta, J.R. & A.E Almirón (2004):
Astyanax chico sp.n. – a new species from the río San Francisco basin, northwest of Argentina (Teleostei: Characiformes: Characidae).
Zoologische Abhandlungen des Staatlichen Museums für Tierkunde, Dresden 54: 11-17