title: An unusual oviraptorosaurian dinosaur from China.
abstract: Oviraptorosaurians are an unusual group of theropod dinosaurs, with highly specialized skulls. Here we report a new oviraptorosaurian, Incisivosaurus gauthieri, gen. et sp. nov., from the lowest part of the Lower Cretaceous Yixian Formation of China. This oviraptorosaurian displays a number of characters closer to more typical theropods, such as a low skull and toothed jaws, thus greatly reducing the morphological gap between oviraptorosaurs and other theropods. Incisivosaurus has a pair of premaxillary teeth resembling rodent incisors and small, lanceolate cheek teeth with large wear facets. These dental features were previously unknown among theropods and suggest a herbivorous diet. The new discovery provides a case of convergent evolution and demonstrates that non-avian theropods were much more diverse ecologically than previously suspected.
authors.affiliation: Institute of Vertebrate Paleontology & Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China. xing_xu@sina.com
authors.forename: Xing
authors.initials: X
authors.lastname: Xu
authors.forename: Yen-Nien
authors.initials: YN
authors.lastname: Cheng
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Wang
authors.forename: Chun-Hsiang
authors.initials: CH
authors.lastname: Chang
mesh_terms: D000818:Animals; D002681:China; D003817:Dentition; D004032:Diet; D025061:Dinosaurs / Q000033:anatomy & histology* / Q000145:classification; D005580:Fossils; D007568:Jaw / Q000033:anatomy & histology; D010802:Phylogeny; D012886:Skull / Q000033:anatomy & histology; D014070:Tooth / Q000033:anatomy & histology