A latest Ordovician Hirnantia brachiopod fauna from western Yunnan, Southwest China and its paleobiogeographic significance

Huang, Bing; Zhou, Hang-Hang; Harper, David A.T.; Zhan, Ren-Bin; Zhang, Xiao-Le; Chen, Di; Rong, Jia-Yu

Abstract

A new, high-diversity, latest Ordovician brachiopod fauna of nearly 800 brachiopod specimens was collected from the Wanyaoshu Formation (Hirnantian) in the Shaodihe section, Mangshi City, western Yunnan, Southwest China. Altogether 22 genera and two undetermined taxa were identified; dominant are Aegiromena, Anisopleurella, Fardenia, Dalmanella, Hirnantia and Hindella, less common, Paromalomena, Leptaena, Eostropheodonta, Cliftonia, Kinnella, Templeella and Plectothyrella, together with some rare Petrocrania, Xenocrania, Pseudopholidops, Palaeoleptostrophia, Skenidioides, Giraldibella, Draborthis, Dolerorthis and Toxorthis. This is one of the most diverse typical Hirnantia faunas, associated with the Kosov Province. The paleobiogeographic relationships between western Yunnan (Southwest China), Myanmar, Yichang (Central China), Tibet (Southwest China) and Kazakhstan are clarified using Network Analysis and NMDS. The fauna studied is most similar to that of Myanmar; both resided on the Sibumasu terrane. However, the recalculated network diagram, when including the data of Hirnantia fauna from the Prague Basin, indicates that the latter is more closely linked to that of western Yunnan, a testament to the very weak brachiopod provincialism during the Hirnantian, mainly due to the influence of dominant cosmopolitan taxa. Some species of the fauna display significant population variation. Two of the dominant taxa, Aegiromena and Anisopleurella are systematically described, whereas the other two common taxa, Fardenia and Hirnantia are measured and their outlines and internal structures analyzed.

Citation

Huang, B., Zhou, H., Harper, D. A., Zhan, R., Zhang, X., Chen, D., & Rong, J. (2020). A latest Ordovician Hirnantia brachiopod fauna from western Yunnan, Southwest China and its paleobiogeographic significance. Palaeoworld, 29(1), 31-46. https://doi.org/10.1016/j.palwor.2019.03.002

• Journal Article Type: Article
• Acceptance Date: Mar 22, 2019
• Online Publication Date: Mar 27, 2019
• Publication Date: Mar 31, 2020
• Deposit Date: Apr 2, 2019
• Publicly Available Date: Sep 27, 2020
• Journal: Palaeoworld
• Print ISSN: 1871-174X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 29
• Issue: 1
• Pages: 31-46
• DOI: https://doi.org/10.1016/j.palwor.2019.03.002
• Public URL: https://durham-repository.worktribe.com/output/1304859