[3] Epps and Bolaños (2017) accept the unity of the four Nadahup languages, but do not consider Puinave to be related.

[4] Jolkesky (2016) notes that there are lexical similarities with the Arawa, Guahibo, and Tupi language families due to contact.

[5] A discussion of lexical and phonological correspondences between the Nadahup (Vaupés-Japurá) and Tupi languages can be found in Jolkesky and Cabral (2011).

Nadeb and Kuyawi, Hup and Yahup, and Nukak and Kakwa, however, share 90% of their vocabulary and are mutually intelligible, and so are separate languages only in a sociolinguistic sense.

These four branches are not close: Although the family was first suggested in 1906, only 300 cognates have been found, which include pronouns but no other grammatical forms.