Yamaceratops dorngobiensis

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Makovicky, P.J. & M.A. Norell, 2006. Yamaceratops dorngobiensis, a new primitive ceratopsian (Dinosauria: Ornithischia) from the Cretaceous of Mongolia. American Museum Novitates 3530: 1-42.

ABSTRACT: A new basal neoceratopsian taxon from the eastern Gobi Desert is described. Yamaceratops dorngobiensis, tax. nov., is probably of late Early
Cretaceous age, and occupies a phylogenetic position intermediate between Liaoceratops and Archaeoceratops. It is the most basal taxon to display a number of traditional neoceratopsian synapomorphies concentrated in the
cheek region and mandible. These include presence of an epijugal, lateral displacement of the coronoid process, a lateral ridge on the surangular for insertion of the jaw adductors, and a lateral wall to the mandibular glenoid. Yamaceratops shares two synapomorphies (tubercles on the ventral edge of the angular and shape of the jugal) with Liaoceratops, indicating
that the transient presence of derived characters may be prevalent in the early evolutionary history of Ceratopsia. Yamaceratops shares aspects of frill morphology with Liaoceratops and Leptoceratops that suggest a function
unrelated to display for this anatomical structure in basal
neoceratopsians, and hints at a more complex evolutionary history for ceratopsian frills. Considerations of patristic distances and mosaic evolution among basal neoceratopsian taxa indicate that a greater diversity of these animals remains undiscovered.

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Alors vivement l'artcle

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Sujet déplacé

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Non ,pas déplacé car je suis en train de telecharger le pdf sur rapid share ,alors c'est chez documents

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Mais si mais si car ceci est une news ...
Fatigué non Mark?

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Oki voici le lien

http://rapidshare.de/files/33109077/Yamaceratops_dorngobiensis.pdf.html



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Edité le 14/09/2006 à 20:29 par lolo

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... Edit: lien édité ...

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Edité le 14/09/2006 à 20:29 par lolo