Stuck between rivers: a new species of Ctenomys from northern Argentine Patagonia

Abstract

Ctenomys (tuco-tucos) is one of the most speciose genera of mammals, with around 70 described species. Recently, therate of new species descriptions within the genus Ctenomys has notably increased, primarily due to recent taxonomic revisionsand surveys in previously unexplored geographic areas. In this study, utilizing both morphological and molecularevidence, we describe a new species of Ctenomys from northern Argentine Patagonia, confined between the Colorado andNegro rivers. This new species is a member of the Magellanicus group displaying close relationships with other speciesdistributed in northern Patagonia and adjacent regions (C. bidaui, C. miguelchristie, C. pontifex, and C. pulcer). The majorrivers in the region (Colorado and Negro rivers) appear to delineate the distributional boundaries of the identified taxa. Wetherefore propose that rivers, acting as natural barriers to dispersal, have significantly influenced the diversity of Ctenomysin northern extra-Andean Patagonia.