450 in Peru (2000 SIL). 70% monolingual. 300 Mastanahua. Population total all countries: 453.
Upper Purús river area. Also in Brazil.
5 (Developing). Recognized language (1993, Constitution, Article 48).
Home on Purus River. All ages. Some intermarry with and use Spanish [spa] at home. Those with schooling use varying degrees of Spanish.
Christian, traditional religion.