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.
Potamotrygon
River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family Potamotrygonidae in the order Myliobatiformes, one of the four orders of batoids, cartilaginous fishes related to sharks. They are found in rivers in tropical and subtropical South America. A single marine genus, Styracura, of the tropical West Atlantic and East Pacific are also part of Potamotrygonidae. They are generally brownish, greyish or black, often with a mottled, speckled or spotted pattern, have disc widths ranging from 31 to 200 centimetres (1.0–6.6 ft) and venomous tail stingers. River stingrays feed on a wide range of smaller animals and the females give birth to live young. There are more than 35 species in five genera.
Potamotrygonidae
Potamotrygon histrix is one of the most southernly distributed river stingrays, being found in the Río de la Plata Basin
Potamotrygon henlei and its close relatives (e.g., P. leopoldi) mainly feed on snails in the wild, but easily adapt to a more generalized diet in captivity
As in other rays, this Plesiotrygon iwamae is easily identified as male by its claspers, the pair of elongated structures at the base of the tail
