ACKNOWLEDGEMENTS
This work was supported by the National Natural Science Foundation of
China (31470312; 31470319; 31970231), Science and Technology Planning
Project of Guangdong Province, China (2016A030303048). We thank Xiaolan
Wang, Juan Zhou, Bo Li, Yemei Huang, and Zhong Zhang for help with
sampling and field trips. We thank Zhixia Sun, Mark Ravinet, Joana
Meier, Tongjian Liu, Huiqin Yi, and Haifei Yan for data analyses.
Special thank goes to Prof. Qi Wang for providing fossil information.