Potamotrygon is a genus of freshwater stingrays in the family Potamotrygonidae native to the rivers of South America, and sometimes seen in the aquarium trade. It inhabits rivers of tropical and subtropical climates, especially those of the Amazon basin and is virtually present in all South American countries, except for Chile.

Like other stingrays, the fishes of this genus have venomous barbs at the base of their tails, and their stings are dangerous to humans. It is said that the natives of South America fear the stingray more than they do fear the piranha.

Potamotrygon vary considerably in color, pattern and size, with the maximum disc width ranging from 31 cm (1 ft) in P. wallacei to 1.5 m (5 ft) in P. brachyura.

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