A large number of languages known only from brief mentions are thought to have been Uto-Aztecan languages, but became extinct without being documented. The following list is based on Campbell (1997:133–135).
Cahuameto:[4] probably belongs with Oguera and Nio
Cazcan (Caxcan): sometimes considered to be the same as Zacateca, although Miller (1983) would only consider these to be geographical classifications.
Chínipa: may be a Tarahumaran language close to Ocoroni, since colonial sources claim the two are mutually intelligible. It may also instead be a local name for a variety of Guarijío.
Concho:[5] probably a Taracahitic language (Troike 1988). Subdivisions include Chinarra[6], Abasopalme,[7]Chizo; Toboso is possibly related to Concho as well.
Conicari:[8] a Taracahitic language closely related to Tahue
Giamina/Omomil:[9] Kroeber (1907) and Lamb (1964) believe Giamina may constitute a separate branch of Northern Uto-Aztecan, although Miller (1983) is uncertain about this. It was spoken in Southern California.
Guasave: possibly a Taracahitic language, or may instead be non-Uto-Aztecan language possibly related to Seri due to the speakers' maritime economy (Miller 1983). Dialects include Compopori, Ahome, Vacoregue, and Achire.
Guazapar (Guasapar):[10] probably a Tarahumara dialect, or it may be more closely related to Guarijío and Chínipa. Guazapar, Jova, Pachera, and Juhine may possibly all be dialects of Tarahumara.
Guisca (Coisa)
Hio: possibly a Taracahitic language
Huite: closely related to Ocoroni, and may be Taracahitic
Irritila: a Lagunero band
Jova (Jobal, Ova):[11] most often linked with Opata, although some scholars classify it as a Tarahumara dialect. Miller (1983) considers it to be "probably Taracahitan."
Jumano;[12] also Humano, Jumana, Xumana, Chouman (from a French source), Zumana, Zuma, Suma, and Yuma. Suma is probably the same language, while Jumano is possibly Uto-Aztecan. (Not to be confused with the Jumana language of Colombia.)
Lagunero: may be the same as Irritila, and may also be closely related to Zacateco or Huichol.
Naarinuquia (Themurete?): Uto-Aztecan affiliation is likely, although it may instead be non-Uto-Aztecan language possibly related to Seri due to the speakers' maritime economy.[13]
Nio: completely undocumented, although it is perhaps related to Ocoroni.
Ocoroni: most likely a Taracahitic language, and is reported to be mutually intelligible with Chínipa, and similar to Opata. Related languages may include Huite and Nio.
Tecual: closely related to Huichol. According to Sauer (1934:14), the "Xamaca, by another name called Hueitzolme [Huichol], all ... speak the Thequalme language, though they differ in vowels."
Xixime (Jijime): spoken by the Xiximes, possibly a Taracahitic language. Subdivisions are Hine and Hume. Its links with Acaxee are uncertain.
Zacateco: often considered the same as Acaxee, although this is uncertain. It is possibly related to Huichol, although Miller (1983) leaves it as unclassified.
Zoe: possibly a Taracahitic language, with Baimena as a subdivision. It is possibly affiliated with Comanito.
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Amotomanco". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Alternate spellings include Cahuimeto or Cahuemeto.[3]
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Concho". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Clark, Patricia Roberts (21 October 2009). Tribal Names of the Americas: Spelling Variants and Alternative Forms, Cross-Referenced. McFarland. p. 10. ISBN978-0-7864-5169-2.
^Alternate spellings include Concuari or Conicare.[3]
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Omomil". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Guazapar". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Jova". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Jumano". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
^Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2017). "Tanpachoa". Glottolog 3.0. Jena, Germany: Max Planck Institute for the Science of Human History.
Miller, Wick R. (1983). "Uto-Aztecan languages". In Ortiz, Alfonso (ed.). Handbook of North American Indians. Vol. 10. Washington, D.C.: Smithsonian Institution. pp. 113–124.
Troike, Rudolf C. (1988). "Amotomanco (Otomoaca) and Tanpachoa as Uto-Aztecan languages". International Journal of American Linguistics. 54: 235–241. doi:10.1086/466084.