Xingu River ray mostly brownish-dusky (large white center to underparts of "P. henlei"). Compared to "P. albimaculata", "P. leopoldi" has fewer and larger yellowish-white spots above. Xingu River ray The Xingu River ray, white-blotched river stingray, or polka-dot stingray ("Potamotrygon leopoldi") is a species of freshwater fish in the family Potamotrygonidae. It is endemic to the Xingu River basin in Brazil and prefers rocky bottoms. It is sometimes kept in aquaria. "P. leopoldi" reaches up to in disc width, in total length and in weight. Females grow larger than males. It is closely related to the similar "P. henlei" from the Tocantins River
River tyrannulet mostly contiguous stretches, about 100 to 150 km in width. The rivers in the Amazon Basin, going upstream are the following: Amazon River, (Tocantins, Araguaia— east of the Xingu), Xingu River, Madeira, and Marañón-Ucayali, (in Amazonian Peru). For the Araguaia River, the bird's range continues only downstream to the Tocantin confluence, then down the Tocantins to the Pacific, (500 km east of the Amazon River outlet; the Xingu River confluence range connects to the Tocantins range.) On the Madeira River, from Amazonian Bolivia, the range only extends into the country by 300 km of the 2300 km Madeira River range.