Work in progress. Used in education and government. Bible portions 1514-1985. Chaco, northwestern border area, Laguna Negra reservation. Some are bilingual in Spanish.
Speakers have reservations about use of their language except within their culture.
Mataco-Guaicuru , Guaicuruan. Bible portions 1964-1967. They are reported to speak a 'poor' variety of Paraguayan Guarani. Young people speak Toba-Maskoy and learn some Spanish in school. Country Studies Part of the Ethnologue , 13th Edition, Barbara F. Grimes, Editor.