Cricetidae (Rodentia, Mammalia) from the early miocene site of els casots (Vallés-Penedés Basin, Catalonia)

© 2017, National Museum Prague. All rights reserved. Els Casots is an extremely rich early Miocene site located in the Vallès-Penedès Basin (Catalonia, Spain) that has provided both micro- and macrovertebrates. However, the small mammals have been poorly studied. In this work we describe the cricetid fauna from els Casots and provide further insights into the chronology of the site. The cricetids are very common and include the species Megacricetodon primitivus and Democricetodon hispanicus. A second, larger-sized Democricetodon species is also represented by just one molar. The presence of M. primitivus together with the eomyid Ligerimys ellipticus indicates a correlation to zone MN 4 and to the local zone C of the Calatayud-Montalbán Basin (Aragón, east-central Spain), the type area of the Aragonian mammal age. This is further supported by the presence of two different Democricetodon species. A correlation to the local subzones of that area is attempted, but unfortunately the cricetid succession is not the same in both basins. However, the fact that L. ellipticus is the only eomyid species present at els Casots would indicate that this site is somewhat younger than other MN 4 localities from the Vallès-Penedès, where this species coexists with its ancestor Ligerimys florancei.