Note on two fresh-water sting-rays species (Condrichthyes, Potamotrygonidae): a. Redescription of Potamotrygon schroederi, Yepez 1957. b. Designation of two paratypes of P. pauckei, Castex 1963 and their description. Acta Scientifica, Universidad del Salvador, 9, 1–26
Potamotrygon castexi (Condrichthyes, Potamotrygonidae), a new species of freshwater sting-ray for the Paraná River. Acta Scientifica, Universidad del Salvador, 6, 1–21, 1 pl.
