Revision of Cricetodon soriae (Rodentia, Mammalia), New Data from the Middle Aragonian (Middle Miocene) of the Calatayud-Daroca Basin (Zaragoza, Spain)

Abstract

The oldest record of Cricetodon (Cricetidae, Rodentia, Mammalia) from the Aragonian type area (Calatayud-Daroca Basin, Zaragoza, Spain) is described. The remains from Las Umbrías (LUM) and Las Planas (LP) sections are attributed to Cricetodon soriae, described in the locality Somosaguas N (SOMN) from the Madrid Basin (biozone E, MN5). The studied material (including 52 jugal teeth) belongs to eight localities spanning a time interval from 14.06 to 13.80 Ma, covering the entire biozone E. A morphometric analysis of the Calatayud-Daroca material provides the most specific and detailed descriptions of C. soriae until now. New complete descriptions of the type material from SOMN and an emended diagnosis of C. soriae are presented. Comparisons with all the species of Cricetodon described to date have been made. Differences between Cricetodon aureus and Cricetodon meini are discussed; the results yielded by the study of more than 100 upper third molars from Vieux-Collonges make it possible, for the first time, to distinguish between those of C. aureus and C. meini, and to compare them both with C. soriae. The presence of common characteristics indicates a closer relationship of C. soriae with the species of Cricetodon from Asia Minor than with the first representatives of Cricetodon in central and eastern Europe. The distribution of C. soriae in the Iberian Peninsula is coincident with the global cooling event and the increasing in aridity in southwestern Europe, and the faunal dispersion event called Conohyus/Pliopitechus that took place during the local biozone E.