Abstract
Based on a 3D reconstruction, a partial “symmetrodontan” skull from the Yixian Formation, Lujatun Member (Jehol Group) in northeastern China, is assigned to Maotherium sinense. The skull is preserved three-dimensionally including the right mandible, and parts of the maxilla, as well as two upper and eight lower teeth. The dental formula of the studied specimen is ?I, C, 2P, 4M/?i, c, 3p, 5m, and it lacks an m6 which is present in the holotype of M. sinense. No developing teeth inside the maxilla and mandible have been detected, and according to the almost unworn condition of the teeth, the specimen is a young adult. Our studied specimen and Zhangheotherium quinquecuspidens have the same postcanine tooth count of 2P/3p and 4M/5m. Among zhangheotheriids, the early diverged Kiyatherium and Anebodon have a higher number of premolars and a lower number of molars, whereas it is vice versa for the more derived Maotherium and Zhangheotherium.
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Acknowledgements
We thank the Yizhou Fossil and Geology Park for loaning the studied specimen (YFGP 1724), G. Oleschinski for photography, and Z.-X Luo and K. Jäger for discussions and suggestions. TP was supported by a grant of the Studienstiftung des deutschen Volkes. We are grateful to the reviewers A.O. Averianov, R.L. Cifelli, as well as to the editors T. Mörs and M. Reich for their comments, which greatly improved our article.
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Plogschties, T., Martin, T. New information on the maxilla, dentary, and dentition of Maotherium sinense, with comments on the zhangheotheriid dental formulae. PalZ 94, 155–165 (2020). https://doi.org/10.1007/s12542-019-00460-3
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DOI: https://doi.org/10.1007/s12542-019-00460-3