On the systematics of Iberomys Chaline, 1972 (Arvicolidae, Rodentia, Mammalia) from the Lower Pleistocene of the Sierra de Atapuerca (Burgos, España)

The Iberomys lineage is represented by the species I. huescarensis (Ruiz Bustos, 1988), at the lower levels (TD3 to lower TD8) of Trinchera Dolina (Sierra de Atapuerca, Burgos), and not by I. brecciensis Ciebel, 1847 as stated previously. Both species mainly differ in the communication of triangles T4 and T5 of the first lower molar dental pattern, broad in I. huescarensis and narrow in I. brecciensis. I. huescarensis is the ancestral species of the I. brecciensis-cabrerae lineage, and characterizes the late Lower Pleistocene and the transition Lower-Middle Pleistocene in the Iberian Peninsula