Review of three neglected species of Ctenomys (Rodentia: Ctenomyidae) from Argentina

Ctenomys is one of the most speciose genera among South American rodents, whose systematics have not yet been fully elucidated. One of the difficulties for clarifying the identity of its species is the limited information available on some of them, erected more than a century ago and of which only the original descriptions are known, generally very poorly detailed. Our study provides new information about Ctenomys coludo Thomas 1920, based on the collection of topotype specimens that allowed us to perform more detailed morphological and molecular analyses, and to compare them with the available information referred to the holotype, with specimens deposited in museum collections, and other species of the genus that have been proposed as related to C. coludo. Our results allow us to place C. coludo as a member of the mendocinus group, proposing C. famosus Thomas, 1920 as a junior synonym for C. coludo. We also recognize Ctenomys johannis as a valid and full species, and provide unpublished information on it from the collection of specimens at the type locality. Thus, we add new areas for the distribution of these species and present their phylogenetic relationships.