Description of a new tribe of sigmodontine rodents (Cricetidae: Sigmodontinae) with an updated classification for the subfamily

We provide a formal recognition to a tribal level clade composed of Andinomys and Punomys, two extant sigmodontine genera consistent and repeatedly recovered in the phylogenetic analyses of molecular and morphological data. As currently recognized, this tribe is distributed in middle to high elevations in the Andes of Bolivia, Perú, northern Chile, and northwestern Argentina in habitats that range from high elevation grasslands and ecotonal areas to dry Puna. Within this new clade Punomys appears as the more specialized member as it is fully restricted to rocky outcrops and their immediate surrounding areas at elevations above 4400 m on both sides of the Altiplano. In contrast, Andinomys occupies a broad elevational range (500 to 4000 m) and multiple habitats, from subtropical mountain forests and semiarid Puna and Prepuna to high altitudinal grasslands. Both taxa share a number of possible synapomorphies (e.g., presence of caudal enlargement of the post-zygapophysis in the second