New genetic data unveil taxonomic complexity in the high-Andean sigmodontine Abrothrix andina (Rodentia, Cricetidae)

The cricetid rodent Abrothrix andina purportedly comprises five taxa, described from specimens collected across three countries, spanning approximately 20 degrees of latitude. This classification, largely based on morphological studies conducted in the early 20th century, has not been reassessed using modern techniques. The preliminary results presented here indicate substantial variation in the cytochrome b gene among populations from Argentina, Chile, and Peru. Notably, Akodon (Abrothrix) gossei, described from the Argentine provinces of La Rioja, Mendoza, and San Juan, emerges as a potentially valid species. Furthermore, the single sequence previously believed to represent typical A. andina populations was found to be misidentified and instead corresponds to Abrothrix olivacea. Therefore, a crucial step in clarifying the complex taxonomic and nomenclatural status of A. andina is to conduct a genetic assessment of animals from the high Andes near Santiago, Chile.