Revisiting Ursus etruscus (Carnivora, Mammalia) from the Early Pleistocene of Greece with description of new material

摘要

The Villafranchian ursids of Greece are scanty, represented by a few isolated teeth and bones. During our last field campaigns in the Mygdonia Basin (Macedonia, Greece) we discovered an almost complete cranium, as well as some cranial, dental and postcranial remains, which are presented in this article. The new material originates from the locality Tsiotra Vryssi (TSR), dated to the late Villafranchian (1.8-1.2 Ma). The specimens are described and compared with ursids from various European localities; their morphological characters and dimensions place it with Ursus etruscus Cuvier, 1823, while the dental features are most similar to the specimens from Pietrafitta (Italy). The TSR cranium was CT-scanned in order to create a 3D virtual model and study its internal anatomy. Its observed endocranial traits exhibit primitive conditions, confirming the basal position of U. etruscus among the Pleistocene European ursids. Most of these features are shared with U. arctos and clearly differ from U. deningeri and U. spelaeus. Finally, we provide a revision of the known Greek material of U. etruscus and the biostratigraphic distribution of the Miocene-Pleistocene ursids of Greece. The earliest secure appearance of Ursus etruscus in Greece is found in the locality Dafnero 1 (Western Macedonia), dated to the end of the middle Villafranchian at similar to 2.0 Ma, whereas its probable last occurrence is known from the locality Apollonia 1 of the Mygdonia Basin, dated to the latest Villafranchian at similar to 1.2 Ma. (C) 2017 Elsevier Ltd and INQUA. All rights reserved.