A new early branching armored dinosaur from the Lower Jurassic of southwestern China.

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  • Additional Information
    • Source:
      Publisher: eLife Sciences Publications, Ltd Country of Publication: England NLM ID: 101579614 Publication Model: Electronic Cited Medium: Internet ISSN: 2050-084X (Electronic) Linking ISSN: 2050084X NLM ISO Abbreviation: Elife Subsets: MEDLINE
    • Publication Information:
      Original Publication: Cambridge, UK : eLife Sciences Publications, Ltd., 2012-
    • Subject Terms:
      Dinosaurs*/anatomy & histology; Animals ; Biological Evolution ; China ; Fossils ; Phylogeny ; Skull/anatomy & histology
    • Abstract:
      The early evolutionary history of the armored dinosaurs (Thyreophora) is obscured by their patchily distributed fossil record and by conflicting views on the relationships of Early Jurassic taxa. Here, we describe an early diverging thyreophoran from the Lower Jurassic Fengjiahe Formation of Yunnan Province, China, on the basis of an associated partial skeleton that includes skull, axial, limb, and armor elements. It can be diagnosed as a new taxon based on numerous cranial and postcranial autapomorphies and is further distinguished from all other thyreophorans by a unique combination of character states. Although the robust postcranium is similar to that of more deeply nested ankylosaurs and stegosaurs, phylogenetic analysis recovers it as either the sister taxon of Emausaurus or of the clade Scelidosaurus + Eurypoda. This new taxon, Yuxisaurus kopchicki , represents the first valid thyreophoran dinosaur to be described from the Early Jurassic of Asia and confirms the rapid geographic spread and diversification of the clade after its first appearance in the Hettangian. Its heavy build and distinctive armor also hint at previously unrealized morphological diversity early in the clade's history.
      Competing Interests: XY, PB, LY, XX, SB No competing interests declared
      (© 2022, Yao et al.)
    • References:
      Science. 1999 Jun 25;284(5423):2137-47. (PMID: 10381873)
      Nat Ecol Evol. 2021 Dec;5(12):1576-1581. (PMID: 34556830)
      Biol Rev Camb Philos Soc. 2014 Aug;89(3):588-617. (PMID: 24251809)
      Nature. 2017 Mar 22;543(7646):501-506. (PMID: 28332513)
      Biol Lett. 2020 Aug;16(8):20200417. (PMID: 32842895)
      Sci Rep. 2017 Feb 16;7:42778. (PMID: 28202910)
      Proc Biol Sci. 2014 Sep 22;281(1791):20141147. (PMID: 25100698)
      PeerJ. 2015 Dec 22;3:e1523. (PMID: 26713260)
      PLoS One. 2013 Dec 02;8(12):e80405. (PMID: 24312471)
      R Soc Open Sci. 2021 Jul 21;8(7):201676. (PMID: 34295511)
      PeerJ. 2015 Dec 21;3:e1494. (PMID: 26713245)
      Sci Rep. 2020 Jul 3;10(1):10961. (PMID: 32620800)
      PLoS One. 2015 Oct 14;10(10):e0138352. (PMID: 26466098)
    • Contributed Indexing:
      Keywords: Ankylosauromorpha; Thyreophora; armoured dinosaur; ecology; evolutionary biology
      Local Abstract: [plain-language-summary] From the plated Stegosaurus to the tank-like Ankylosaurus , armoured dinosaurs are some of the most extraordinary creatures to have roamed the earth. Fossils from this group are abundant from the Late Jurassic period, 155 million years ago, up until the end of the age of the dinosaurs. However, only a few fossils exist from the early part of the Jurassic, making it difficult to understand how these fantastic beasts came to be. More early fossils could help to fill in gaps about armoured dinosaur biology and evolution. Yao et al. describe the anatomy of a new armoured dinosaur, baptized Yuxisaurus , which was found in rocks of Early Jurassic age in southwestern China. Covered in sharp spines, this medium-sized animal was much sturdier and stockier than its immediate relatives, suggesting that the ancestors of Stegosaurus and Ankylosaurus had a wider variety of body forms than once thought. Its presence in China also shows that armoured dinosaurs spread across the world early in their history. Yuxisaurus could help researchers to understand how million years of evolution produced the armoured species we are more familiar with today. As more fossils may emerge from the rocks of southwestern China, it could become possible to further piece together early dinosaur evolution.
    • Publication Date:
      Date Created: 20220315 Date Completed: 20220429 Latest Revision: 20220429
    • Publication Date:
      20240829
    • Accession Number:
      PMC8929930
    • Accession Number:
      10.7554/eLife.75248
    • Accession Number:
      35289749