Paläontologische Zeitschrift

, Volume 69, Issue 3–4, pp 467–473 | Cite as

Unusual aetosaur armor from the Upper Triassic of West Texas, U.S.A.

  • Spencer G. Lucas
  • Andrew B. Heckert
  • Adrian P. Hunt
Article

Abstract

We report two unusual aetosaur scutes from the Tecovas Member of the Dockum Formation, Chinle Group (upper Carnian) of Crosby County, Texas, U.S.A. Originally collected by University of Michigan expeditions in the 1920’s, these scutes cannot be assigned with certainty to any known species of aetosaurs known from the American Southwest. One of these scutes may be a cervical horn ofParatypothorax, and if so confirms the similarities of this aetosaur toDesmatosuchus in the possession of horned lateral spikes. The other is a paramedian scute of a new aetosaur taxon inadequately known at present to be assigned a formal name. These scutes indicate that aetosaurs were more diverse in the Chinle Group than currently known, but do not alter the robust Late Triassic biochronology based on aetosaurs.

Kurzfassung

Zwei ungewöhnliche Hautknochen-Schilder aus dem Tecovas Member der Dockum Formation, Chinle Group (oberes Karn) von Crosby County (Texas, USA) werden beschrieben. Ein Schild ist wohl ein zervikales Horn vonParatypothorax. Das andere ist ein paramedianes Schild eines neuen Aetosauriers, dem allerdings aus Mangel an Information kein formeller Name gegeben wird. Die Schilder zeigen, daß die Diversität der Aetosaurier in der Chinle Group höher war als bisher angenommen. Die auf Aetosauriern basierende Biochronologie der Oberen Trias ändert sich durch die Neufunde nicht.

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References

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Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 1995

Authors and Affiliations

  • Spencer G. Lucas
    • 1
  • Andrew B. Heckert
    • 2
  • Adrian P. Hunt
    • 3
  1. 1.New Mexico Museum of Natural History and ScienceAlbuquerqueUSA
  2. 2.Department of Earth and Planetary SciencesThe University of New MexicoAlbuquerqueUSA
  3. 3.Department of GeologyUniversity of Colorado at DenverDenverUSA

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