A Mesozoic fossil lagerstätte from 250.8 million years ago shows a modern-type marine ecosystem.

Xu Dai (1, 2) , Joshua H.F.L. Davies (3) , Zhiwei Yuan (1) , Arnaud Brayard (2) , Maria Ovtcharova (4) , Guanghui Xu (5, 6) , Xiaokang Liu (1) , Christopher P.A. Smith (2) , Carrie E. Schweitzer (7) , Mingtao Li (8) , Morgann G. Perrot (3, 9) , Shouyi Jiang (1) , Luyi Miao (1) , Yiran Cao (1) , Jia Yan (1) , Ruoyu Bai (10) , Fengyu Wang (1) , Wei Guo (1) , Huyue Song (1) , Li Tian (1) , Jacopo Dal Corso (1) , Yuting Liu (1) , Daoliang Chu (1) , Haijun Song (1)

1 State Key Laboratory of Biogeology and Environmental Geology
2 BGS - Biogéosciences [UMR 6282]
3 SCTA - Département des sciences de la terre et de l'atmosphère [Montréal]
4 Department of Earth Sciences [Geneva]
5 Key Laboratory of Vertebrate Evolution and Human Origins
6 CAS Center for Excellence in Life and Paleoenvironment
7 Department of Earth Sciences
8 Institute of Geology and Paleontology
9 GEOTOP - Centre de recherche sur la dynamique du système Terre
10 Henan University of Engineering

Finely preserved fossil assemblages (lagerstätten) provide crucial insights into evolutionary innovations in deep time. We report an exceptionally preserved Early Triassic fossil assemblage, the Guiyang Biota, from the Daye Formation near Guiyang, South China. High-precision uranium-lead dating shows that the age of the Guiyang Biota is 250.83 +0.07/-0.06 million years ago. This is only 1.08 ± 0.08 million years after the severe Permian-Triassic mass extinction, and this assemblage therefore represents the oldest known Mesozoic lagerstätte found so far. The Guiyang Biota comprises at least 12 classes and 19 orders, including diverse fish fauna and malacostracans, revealing a trophically complex marine ecosystem. Therefore, this assemblage demonstrates the rapid rise of modern-type marine ecosystems after the Permian-Triassic mass extinction.

Domaines: Paléontologie

Xu Dai, Joshua H.F.L. Davies, Zhiwei Yuan, Arnaud Brayard, Maria Ovtcharova, et al.. A Mesozoic fossil lagerstätte from 250.8 million years ago shows a modern-type marine ecosystem.. Science, 2023, 379 (6632), pp.567-572. ⟨10.1126/science.adf1622⟩. ⟨hal-04016004⟩