Siouan languages
Siouan languages can be grouped into the Western Siouan languages and Catawban languages. The Western Siouan languages can be divided into Missouri River languages (such as Crow and Hidatsa), Mandan, Mississippi River languages (such as Dakotan, Chiwere-Winnebago, and Dhegihan languages), and Ohio Valley Siouan branches. The Catawban languages consist only of Catawban and Woccon.
Secoya language
The Secoya language has been classified as a member of the Tucanoan linguistic family and the sub-family, Western Tucanoan, in Ecuador and Peru. The remaining sub-families are Eastern Tucanoan and Central Tucanoan, comprising at least fourteen languages spoken in the region of the Vaupés River in Colombia and Brazil. Included among the Secoya are a number of people called Angoteros. Although their language comprises only some dialectal differences of Secoya, there are no other communicative obstacles present. The Siona of the Eno River, linguistically different from the Siona of the Putumayo, say there are significant dialectal differences between their language and Secoya, but are still considered a part of them. In ethnographic publications, the Secoya go by other alternate names as well: Encabellado, Pioje (meaning "no" in Secoya), Santa Maria, and Angutera.