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
American River of the Lakes) which may or may not have been an error, as in those times the area of the Central Valley surrounding the American River was home to vast marshes, which would have given the river the appearance of a series of lakes. During the 1820s, Jedediah Smith led an expedition to the American River with the goal of finding a safe route across the Sierra Nevada. After a failed attempt to cross the mountains via the South Fork of the American River, Smith's group managed to cross via Ebbetts Pass on the headwaters of the Stanislaus River, becoming