The Dormouse-the-swamp is a large rodent of the family of miocastorídeos, found in southern South America. Reddish-brown coat, long tail and thick, covered with scales and hair thinning, living in marshes, ponds and rivers. Also known by the names of Caxingui, nutria Perez Mouse waterline. Sleep during the day. It feeds on grass, roots and aquatic plants and herbs, tubers, leaves, grains, meat and fish. The male cares for the pups at birth, protecting and nurturing female to recover.
Found in South America in Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay. In Brazil, the South Region of São Paulo to Rio Grande do Sul can be found along rivers Tietê and Pinheiros, in Sao Paulo.