High Quality Content by WIKIPEDIA articles! The Xavante River (Mato Grosso) is a river of Mato Grosso state in western Brazil. Mato Grosso is one of the states of Brazil, the third largest in area, located in the western part of the country. Neighboring states are (from west clockwise) Rondônia, Amazonas, Pará, Tocantins, Goiás and Mato Grosso do Sul. It also borders Bolivia to the southwest. A state with a flat landscape, alternating great chapadas and plain areas, Mato Grosso presents three different ecosystems: Cerrado, Pantanal and the Amazon Rainforest.