[5] The name Abrotrichini remained formally unavailable under the International Code of Zoological Nomenclature, however, because their proposal had been conditional.

[6] Thus, the clade remained without a valid name and for this reason it was included in Akodontini in the 2005 third edition of Mammal Species of the World.

[10] The remaining three genera, each of which includes a single species, are closely related and share fossorial (digging) habits.

[4] Abrotrichines are small to medium-sized sigmodontine rodents with long and soft,[1] usually gray or brown[8] fur, a short, hairy tail and large, strong feet with well-developed claws.

[1] A karyotype of 52 chromosomes (2n = 52), present in several species, has been suggested as a synapomorphy of the tribe,[16] but while this possibility is yet to be tested, Pearsonomys is now known to have 2n = 56 and some Abrothrix olivaceus have 2n = 44.