A new species of water vole from the Early Pleistocene of Southern Europe

摘要

In the Early Pleistocene Red Lower Unit of the Sima del Elefante site (Sierra de Atapuerca karst complex, Burgos, Spain), levels TE9TE13, dental and mandibular remains of an arvicoline are referred to as the new species Arvicola jacobaeus sp. nov. The new species has medium-sized hypselodont molars, with abundant cementum in the re-entrant folds, and thick enamel band with differentiation of the Mimomys-type. The occlusal morphology of M3 is simple. The dental morphology of the new species resembles that of Arvicola sapidus, though smaller. It is more derived, in size and morphology than the Middle Pleistocene species Arvicola mosbachensis. The morphologic affinities among Arvicola jacobaeus, Arvicola terrestris, and A. sapidus suggest a common ancestry. A preliminary phylogenetic analysis corroborates that Mimomys savini is the sister group of the Arvicola clade.