Some linguists have suggested that it belonged to the widely scattered Hokan phylum of California and Mexico (Gursky 1966; Swadesh 1967); however, the evidence for this seems inconclusive (Laylander 1997; Zamponi 2004; Mixco 2006).

William C. Massey (1949) suggested a connection with Pericú, but the latter is too meagerly attested to support a meaningful comparison.

Massey (1949), cited in Campbell (1997:169), gives this tentative classification based on similarity judgments given by colonial-era sources, rather than actual linguistic data.

Pronouns were as follows (Golla 2011): The Pater Noster is recorded in Guaycura, with a literal gloss by Pimentel (1874: cap.

Waikuri vocabulary from Zamponi (2004), which was compiled primarily from 18th-century sources by Johann Jakov Baegert,[3] as well as from Lamberto Hostell and Francisco de Ortega:[2]