Heliotrygon rosai, or Rosa's round ray, is a species of freshwater fish in the family Potamotrygonidae. It is native to the Amazon basin (Marajó to Peru) in South America.de Carvalho, M.R. & Lovejoy, N.R. (2011): Morphology and phylogenetic relationships of a remarkable new genus and two new species of Neotropical freshwater stingrays from the Amazon basin (Chondrichthyes: Potamotrygonidae). Zootaxa, 2776: 13–48. Its maximum disc width is and the stinger is greatly reduced, rendering it virtually harmless. It is listed as vulnerable by the IUCN red list.
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