A globally distributed durophagous marine reptile clade supports the rapid recovery of pelagic ecosystems after the Permo-Triassic mass extinction

Qiao, Y; Liu, J; Wolniewicz, AS; Iijima, M; Shen, YF; Wintrich, T; Li, Q; Sander, PM

Abstract

Marine ecosystem recovery after the Permo-Triassic mass extinction (PTME) has been extensively studied in the shallow sea, but little is known about the nature of this process in pelagic ecosystems. Omphalosauridae, an enigmatic clade of open-water durophagous marine reptiles, potentially played an important role in the recovery, but their fragmentary fossils and uncertain phylogenetic position have hindered our understanding of their role in the process. Here we report the large basal ichthyosauriform Sclerocormus from the Early Triassic of China that clearly demonstrates an omphalosaurid affinity, allowing for the synonymy of the recently erected Nasorostra with Omphalosauridae. The skull also reveals the anatomy of the unique feeding apparatus of omphalosaurids, likely an adaptation for feeding on hard-shelled pelagic invertebrates, especially ammonoids. Morphofunctional analysis of jaws shows that omphalosaurids occupy the morphospace of marine turtles. Our discovery adds another piece of evidence for an explosive radiation of marine reptiles into the ocean in the Early Triassic and the rapid recovery of pelagic ecosystems after the PTME. Further evidence for an explosive marine reptile diversification event in the Early Triassic is presented via morphological analysis of a new Sclerocormus specimen.

Citation

Qiao, Y., Liu, J., Wolniewicz, A., Iijima, M., Shen, Y., Wintrich, T., …Sander, P. (2022). A globally distributed durophagous marine reptile clade supports the rapid recovery of pelagic ecosystems after the Permo-Triassic mass extinction. Communications Biology, 5(1), https://doi.org/10.1038/s42003-022-04162-6

• Journal Article Type: Article
• Acceptance Date: Nov 24, 2022
• Online Publication Date: Nov 14, 2022
• Publication Date: 2022
• Deposit Date: Aug 15, 2023
• Publicly Available Date: Aug 15, 2023
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 1
• DOI: https://doi.org/10.1038/s42003-022-04162-6
• Keywords: ANATOMY; OMPHALOSAURUS; DIVERSITY; EVOLUTION; TURTLE