Diversity of Amphicyonidae (Carnivora, Mammalia) in the Middle Miocene Halamagai formation in Ulungur River area, Xinjiang, Northwestern China

ABSTRACT

Amphicyonidae is one of the most widely distributed families of Carnivora in the Early and Middle Miocene, yet the fossil record of this family is extremely poor in Eastern Asia. In this study, we report an unanticipated diversity of Amphicyonidae from the Middle Miocene Halamagai Formation in Ulungur River area, Xinjiang, Northwestern China. At least five species of very different size: Amphicyon ulungurensis (including Amphicyon cf. ulungurensis), Gobicyon zhegalloi, Cynelos cf. bohemicus, Cynelos aff. helbingi and cf. Cynelos sp. based on rare teeth and postcranials were found in the Halamagai Formation. Such diversity of amphicyonids from East Asia is previously unrecorded and indicates the probable presence of a representative Mid-Miocene amphicyonid guild. The geographic location of these species supports the existence of a Palaearctic Neogene faunal exchange of amphicyonids between Europe and East Asia during the early Middle Miocene interval.

KEYWORDS:

• Amphicyon
• Cynelos
• Gobicyon
• Halamagai
• Middle Miocene

Acknowledgments

The authors are thankful to Pro. Zhanxiang Qiu for discussion, providing literature and for his communication of unpublished amphicyonids from Tongxin and Hezheng area. The authors are also thankful to Ms. Jin Chen and Mr. Dongsheng Li in helping to prepare fossil and living specimens for comparisons, and to Mr. Haibing Wang in providing photos of Cynelos from North America. The authors are also thankful to two anonymous reviewers for useful discussion and advice, as well as English improvement. In addition to authors and others listed in the materials and methods section, we also are grateful to Mr. Chao Suo and Mr. Sijian Xu for taking part in the field work. This work was supported by the Chinese Academy of Sciences (Grant Nos. XDPB05), the National Natural Science Foundation of China (Grant Nos. 41430102), the Special Research Program of Basic Science and Technology of the Ministry of Science and Technology (Grant No. 2015FY310100-14), Chinese Natural Science Foundation Program (grant number 41772018) and the Sino-Czech Joint Program (grant number, CAS-17-06).

Declaration of interest statement

All authors declare no conflict of interest.

Additional information

Funding

This work was supported by the Chinese Academy of Sciences [XDPB05]; National Natural Science Foundation of China [41430102]; Sino-Czech Joint Program [CAS-17-06]; Chinese Natural Science Foundation Program [41772018]; Special Research Program of Basic Science and Technology of the Ministry of Science and Technology [2015FY310100-14];