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
East River (South Dakota) East River (South Dakota) The East River portion of South Dakota refers to the section of the state lying east of the Missouri River. Geographical distinctions between the eastern and western sections of the state were reinforced by differing patterns of European-American settlement and Native American resettlement during the 19th and 20th centuries. The eastern half of South Dakota was heavily glaciated and is largely covered by glacial till and loamy soil, which has lent itself to agricultural uses. The Missouri River roughly follows the 100th meridian in the state, and areas to the west of the meridian receive less