Yamaceratops dorngobiensis, a new primitive ceratopsian (Dinosauria, Ornithischia) from the Cretaceous of Mongolia ; American Museum novitates, no. 3530
Supplemental Materials
Date
2006
item.page.datecreated
Journal Title
Journal ISSN
Volume Title
Publisher
New York, NY : American Museum of Natural History
DOI
DOI
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.
Description
42 p. : ill. ; 26 cm.
Includes bibliographical references (p. 33-35).
Includes bibliographical references (p. 33-35).
item.page.type
text