Pisanosaurus mertii and the Triassic ornithischian crisis: could phylogeny offer a solution?

  title={Pisanosaurus mertii and the Triassic ornithischian crisis: could phylogeny offer a solution?},
  author={Matthew G. Baron},
  journal={Historical Biology},
  pages={967 - 981}
  • M. Baron
  • Published 14 September 2019
  • Geography, Environmental Science
  • Historical Biology
Abstract Two recent studies have independently recovered Pisanosaurus mertii – long thought to represent the oldest known member of Ornithischia – within Silesauridae. These finds are expanded upon here, as are the implications of this hypothesis. Based upon these finds, it now appears that Ornithischia was absent in the Triassic Period entirely, which constitutes a major incongruence between the fossil record and current phylogenetic hypotheses, particularly the traditional model of dinosaur… 

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