A new peculiar species of the subterranean rodent Ctenomys (Rodentia, Ctenomyidae) from the Holocene of central Argentina

DE SANTI, N.; PIÑERO, P.; D. RIVERO; VERZI, D.; MORGAN, C.; TONNI, E.; OLIVARES, I.; M. MEDINA

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2020 vol. 100 p. 1 - 10

0895-9811

The subterranean rodent Ctenomys is the single living representative of the family Ctenomyidae, and the most diverse genus within Hystricomorpha. Its fossil record begins in the late Pliocene and shows an increase in diversity since the Pleistocene. Here we describe a new middle-sized Ctenomys species from a large cranial sample collected at the archaeological site Quebrada del Real 1 in the high plains of the Pampa de Achala (Córdoba, Argentina). For this goal, we analyzed the cranial and mandibular shape variation through a geometric morphometric approach, and performed a comparative morphological analysis in the context of the living Ctenomys. The new species is characterized by having a wide rostrum, very deep rostral fossa, strong frontal fossa, major palatine foramina well anteriad to the maxillo-palatine suture, upper incisors strongly procumbent and with grooved enamel, and molars with cement. A phylogenetic analysis demonstrated its close affinity with Ctenomys osvaldoreigi, a living species from a nearby area. Its chronological range extends from 7360 to 300 years B.P., and it represents the first notice of a Holocene extinction for a Ctenomys species.