Looking under stones: A new Ctenomys species from the rocky foothills of the Sierras Grandes of central Argentina

Abstract

Ctenomys (tuco-tucos) is one of the most speciose genera of mammals, and the number of species that compose it continues to increase. Of the 65 species currently recognized for the genus, 15% have been described in the last 10 years. In this work, based on morphological and molecular evidence, we describe a new species of tuco-tuco for Central Argentina. This new species inhabits stony soils in the foothills of Sierras Grandes in Córdoba province and is distinguished from its congeners by a combination of anatomical characters, including a unique morphology of the posterolateral extension of the palatine. The molecular phylogeny based on the mitochondrial cytochrome b gene showed that this new species does not belong to any species complex described for Ctenomys. On the contrary, this new taxon shows a high genetic divergence with the rest of the species and species groups of Ctenomys and was recovered as an independent lineage within the phylogeny of the genus. This finding increases the richness of Ctenomys to 66 species. Our results highlight the need to increase the geographic sampling of studies in this genus to achieve a more complete understanding of its diversity.