Xingliang Zhang, Department of Geology, Northwest University, Xi'an, China.

Zisheng Guo, College of Life Sciences, Northwest University, Xi'an, China.

Wei Liu, Northwest University Museum, Northwest University, Xi'an, China.

Ruliang He, Department of Geology, Northwest University, Xi'an, China.

Luoyang Li, College of Marine Geosciences, Ocan University of China, Qingdao, China.

Weiduo Hao, Department of Geology, Northwest University, Xi'an, China.