Xingu River ray 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 basin and "P. albimaculata" from the Tapajós River basin. Compared to "P. henlei", "P. leopoldi" is deeper black above and its underparts are
Tapajós-Xingu moist forests the ecoregion blends into the Mato Grosso seasonal forests ecoregion. Elevations range from above sea level along the Amazon to in the south. The ecoregion mostly lies on the undulating terrain of the ancient Brazilian Shield. Soils are often rich in nutrients, but poor soils are found in the higher areas. The main rivers are blackwater, with little or no suspended sediment. The largest is the Iriri, a tributary of the Xingu. Others are the Jamanxim, Curuá, Crepori, Curuá Una, and Jaraucu. The ecoregion is in the neotropic ecozone and the tropical and subtropical moist broadleaf forests biome. The Köppen