Paläontologische Zeitschrift

, Volume 64, Issue 3–4, pp 317–328 | Cite as

Re-evalution of “Typothoraxmeadei, a Late Triassic aetosaur from the United States

  • Adrian P. Hunt
  • Spencer G. Lucas
Article

Abstract

Aetosaur specimens from Howard County, Texas, USA, namedTypothorax meadei by Sawin (1947) represent a new genus here namedLongosuchus (type and only species -L. meadei). Longosu-chus is characterised by the possession of seven dentary teeth, a dentary excluded from the ventral margin of the lateral mandibular fenestra and by the angular, spinose lateral scutes throughout the dorsal region with lateral horns which have faceted sides.Longosuchus is found in mid-late Carnian strata in Texas, New Mexico and North Carolina, USA. Aetosaurs can be used to distinguish three successive biochrons in Late Triassic strata of the American Southwest, which are, in ascending order of age, theLongosuchus biochron, theStagonolepis biochron and theTypothorax biochron.

Kurzfassung

Die in Howard County, Texas, USA gefundenen und von Sawin (1947)Typothorax meadei genannten Aetosauria-Exemplare stellen ein neues Genus dar, das wir hier alsLongosuchus einführen. Dieses Genus enthält nur eine einzige Art (L. meadei).Longosuchus ist durch folgende Merkmale charakterisiert: sieben dentale Zähne; ein vom ventralen Rand des lateralen mandibularen Fensters ausgeschlossenes Dentale; stachelige Panzerplatten am ganzen Oberkörper und laterale Hörner mit nicht-zirkulärem Querschnitt.Longosuchus wurde in mittleren bis oberen Carnischen Schichten in Texas, New Mexico und North Carolina, USA, gefunden. Aetosauria können benutzt werden, um drei sukzessive Biochrone in oberen triassischen Schichten des Südwestens von Nordamerika zu unterscheiden. Dies sind, nach absteigendem Alter,Longosuchus Biochron,Stagonolepis Biochron undTypothorax Biochron.

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Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 1990

Authors and Affiliations

  • Adrian P. Hunt
    • 1
  • Spencer G. Lucas
    • 1
  1. 1.New Mexico Museum of Natural HistoryAlbuquerqueUSA

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