Fossils found in western North America reveal a new species of large-bodied, feathered oviraptorosaurian theropod dinosaur from the latest Cretaceous Period, according to a paper published in the open-access journal PLOS ONE on March 19, 2014 by Matthew Lamanna from Carnegie Museum of Natural History in Pennsylvania and colleagues.
Known for their beaks, long necks, and relatively short tails, the bird-like oviraptorosaurian group contains dinosaurs with body sizes ranging from a few kilograms to more than one metric ton. The scientists described three well-preserved partial skeletons from the uppermost Cretaceous Hell Creek Formation of North and South Dakota. Collectively, they include bones from most regions of the skeleton, allowing scientists to extensively analyze the body structure and evolutionary relationships of the animal. The authors demonstrate that the fossils pertain to a new genus and species within the oviraptorosaurian group Caenagnathidae, Anzu wyliei. Previously, scientists knew little about Caenagnathidae due to the highly incomplete nature of nearly all described fossils of this group. "Anzu provides our first good look at an entire group of weird dinosaurs that had been shrouded in mystery for nearly a century," explains Dr. Lamanna.
Anzu wyliei is among the largest known oviraptorosaurs, with an approximate body length of 3.5 m, a height at the hip of 1.5 m, and a body mass of about 200-300 kg. The skull of Anzu is deep and narrow, and is crowned by a tall, cassowary-like crest. The vertebrae indicate the dinosaur had a long neck and a short, thick tail. The shape of the jaw in particular places the dinosaur within the caenagnathid group, with its closest relative being the smaller, geologically older species Caenagnathus collinsi. The jaw shape indicates Anzu was capable of feeding on a variety of food items, including vegetation, small animals, and possibly eggs. Studies of the rocks in which the fossils were found indicate that these dinosaurs may have favored humid floodplain habitats over drier environments.
Citation: Lamanna MC, Sues H-D, Schachner ER, Lyson TR (2014) A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America. PLoS ONE 9(3): e92022. doi:10.1371/journal.pone.0092022
Financial Disclosure: Funding was provided by the Carnegie Museum of Natural History, an American Association of Anatomists Postdoctoral Fellowship, and an American Philosophical Society Franklin Research Grant to E.R.S., and a National Museum of Natural History Peter Buck Postdoctoral Fellowship to T.R.L. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interest Statement: The authors have declared that no competing interests exist.
PLEASE LINK TO THE SCIENTIFIC ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (URL goes live after the embargo ends):http://dx.