A critical re‐evaluation of the Late Triassic dinosaur taxa of North America

  title={A critical re‐evaluation of the Late Triassic dinosaur taxa of North America},
  author={Sterling J. Nesbitt and Randall B. Irmis and William G. Parker},
  journal={Journal of Systematic Palaeontology},
  pages={209 - 243}
Synopsis The North American Triassic dinosaur record has been repeatedly cited as one of the most complete early dinosaur assemblages. The discovery of Silesaurus from Poland and the recognition that Herrerasaurus and Eoraptor may not be theropods have forced a re‐evaluation of saurischian and theropod synapomorphies. Here, we re‐evaluate each purported Triassic dinosaur from North America on a specimen by specimen basis using an apomorphy‐based approach. We attempt to assign specimens to the… 
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Arizonasaurus and its implications for archosaur divergence
  • S. Nesbitt
  • Biology, Medicine
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 2003
Characteristics of the skeleton of Arizonasaurus show that it belongs to a poorly known group of Middle Triassic archosaurs called the ctenosauriscids, and that cteno-poposaurs are or are closely related to poposaurs, which suggests that the divergence of birds and crocodiles occurred earlier than previously thought.