Udanoceratops

Phylogeny: Dinosauria > Ornithischia > Genasauria > Neornithischia > Cerapoda > Marginocephalia > Ceratopsia > Neoceratopsia > Euceratopsia > Leptoceratopsidae

Overview: Leptoceratopsids were a family of ceratopsians that lived in what is now Asia and North America during the latter part of the Cretaceous. They were more basal than their ceratopsid kin, though in some regions, specifically North America, the two families would coexist in more or less the same regions. Udanoceratops is known from Mongolia, where ceratopsids don’t seem to have lived. In a way, Udanoceratops could be seen as having filled in a niche left vacant by that absence. Most of the leptoceratopsids were small, measuring only two or so meters long, but this dinosaur was up to four meters in length, so significantly larger than any other known member of its family. Fossils of the genus are known from the Djadochta and Barun Goyot Formations, so it lived in an arid environment alongside dinosaurs like Protoceratops, Velociraptor and Oviraptor.

Known fossils of Udanoceratops include most of the skull and a few vertebrae. The skull itself was likely its most notable feature, being quite enormous, though even smaller leptoceratopsids tended to have proportionately large heads. The jaws were remarkably deep, suggesting its beaked jaws had a strong bite. Udanoceratops could snap apart an attacking predator’s legs or arms just as easily as it would a branch or root. Low-lying vegetation would’ve made up most of its diet, though how much was available likely depended on the time of year. More derived ceratopsid taxa, such as the ceratopsids or even Protoceratops, often had large skull frills. Udanoceratops and those in its family tended to lack such frills, having at most a ridge of bone. Described in 1992, Udanoceratops takes its name from the Udan Sayr fossil site, where the holotype was first recovered.