Oryza grandiglumis is a type of wild rice of the genus Oryza found in tropical countries of South- and Central- America,: 6 namely Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Paraguay, Venezuela, and Peru. Studied in 1998 in Caño Negro, in northern Costa Rica, it is an annual plant with short rhizomes; its culms can reach 790 centimetres (311 in) and are 4–9 millimetres (5⁄32–23⁄64 in) in thickness. They have developed aerenchyma which allows them to float.
