This work has been funded by the Land and Resources survey project (Grant No. DD20221690 and DD20190524). Guang'an Bureau of Natural Resources provided many conveniences for fossil excavation and protection. We would like to express our heartfelt thanks to Professor Li Daqing from Institute of Paleovertebrate, Gansu Agricultural University, and Professor Lin Li from Chengdu University of Technology, Researcher Peng Guangzhao, Ye Yong and Jiang Shan from Zigong Dinosaur Museum have given us constructive guidance. Special gratitude must be given to Mr. Li Jifei, who kindly provided fossil materials. Two anonymous reviewers have given us valuable comments, which have improved our manuscript greatly. Dr. Susan Turner (Brisbane) and Dr. Qiao Sui assisted with the final manuscript.
Ceratodus is a form genus of ceratodontid lungfishes. Until now, only 14 specimens have been reported from the Mesozoic of China. Detailed measurements and characteristic comparisons based on 15 well-preserved lungfish tooth plates of Ceratodus type, uncovered from the upper member of the Upper Jurassic Shaximiao Formation at Luojiashan, Qianfeng District, Guang'an, Sichuan Province in 2019, allow us to establish a new species, Ceratodus guanganensis sp. nov., on the basis of its small swollen irregular triangular tooth plate with four low and swollen radial crests on the occlusal surface without denticles. Other specimens from the same locality can be referred to C. szechuanensis and C. youngi. This is the first discovery of Ceratodus in the Guang'an region and represents the fifth Ceratodus fossil site in the Sichuan Basin. The discovery indicates that the climate was hot and arid in the Sichuan Basin during the Late Jurassic, and reveals a tectonic paleogeographic relationship between the Yangtze block in southwestern China and the Kola Basin in northern Thailand.
WANG Zizheng, JIANG Xinsheng, WANG Xiaobing, GAO Jianguo, ZHU Sibao.2022. Tooth Plates of Ceratodus (Dipnoi, Ceratodontidae) from the Upper Jurassic Shaximiao Formation of Guang’an, Sichuan Province, China[J]. Acta Geologica Sinica(),96(3):766-775Copy