- Hongshanosaurus
Taxobox
name = "Hongshanosaurus"
fossil_range =Early Cretaceous
regnum =Animal ia
phylum =Chordata
classis =Sauropsid a
superordo =Dinosaur ia
ordo =Ornithischia
infraordo =Ceratopsia
subordo =Cerapoda
familia =Psittacosauridae
genus = "Hongshanosaurus"
species = "H. houi"
binomial = "Hongshanosaurus houi"
binomial_authority = You, Xu, & Wang, 2003"Hongshanosaurus" (pronEng|hɒŋˌʃænəˈsɔrəs hawng-SHAN-o-SAWR-us; "Red Hill lizard") is a
genus ofpsittacosaurid ceratopsian dinosaur from the EarlyCretaceous Period ofeastern Asia . Although twoskull s are the onlyfossil material known, comparisons with close relatives suggest it was a small,biped alherbivore with a bonybeak on the end of both upper and lower jaws. This is one of the many exceptionally well-preserved fossils to be recovered from theYixian Formation ofLiaoning ,China .Discovery and Species
The generic name "Hongshanosaurus" is derived from the
Mandarin Chinese words 紅 ("hóng": "red") and 山 ("shān": "hill"), as well as the Greek word "sauros" ("lizard") . This name refers to the ancientHongshan culture of northeasternChina , who lived in the same general area in which the fossil skull of "Hongshanosaurus" was found."Hongshanosaurus" Species
*"H. houi" (type)The one named
species ("H. houi") honors Hou Lianhai, a professor at theInstitute of Vertebrate Paleontology and Paleoanthropology (IVPP) inBeijing , who curated the specimen. Genus and species were both named by Chinesepaleontologist sYou Hailu ,Xu Xing , andWang Xiaolin in 2003.The
holotype specimen of "Hongshanosaurus" is a juvenile skull, completely preserved except for part of the right side and the tip of the upper jaw. This skull is slightly less than 5centimeters (2 in.) long (You et al. 2003). A much larger adult skull was later described, which is almost 20 centimeters (8 in.) long. It is very similar to skulls of the closely related "Psittacosaurus ", although several differences exist which serve to differentiate the two genera. "Hongshanosaurus" has a lower skull than any species of "Psittacosaurus" and the orbit (eye socket) iselliptical instead of round (You & Xu 2005). These skull were recovered from the Yixian Formation of Liaoning China, which is famous for the exceptional preservation of its fossils, including most of the knownfeathered dinosaurs . The age of this formation has been disputed, but recentlyradiometric dating has confirmed anEarly Cretaceous age, probably in theBarremian stage (130 to 125million years ago ). Several specimens of "Psittacosaurus" have also been recovered from the Yixian, including one with a row of long bristles on the tail which may have had a display function in life. As "Hongshanosaurus" is known only from skull material, it is unknown whether it also had these bristles.Classification
"Hongshanosaurus" was placed in the family Psittacosauridae when it was first described, but has not been included in any phylogenetic analysis since. The only other genus currently classified in this family is "Psittacosaurus" itself, although that genus includes up to a dozen individual species. Psittacosaurids are extremely basal ceratopsians. The more inclusive group Neoceratopsia is in fact defined to include all ceratopsians more
derived than Psittacosauridae (You & Dodson 2004).References
*You H., Xu X. & Wang X. 2003. A new genus of Psittacosauridae (Dinosauria: Ornithopoda) and the origin and early evolution of marginocephalian dinosaurs. "Acta Geologica Sinica" (English edition) 77(1): 15–20.
*You H. & Dodson, P. 2004. Basal Ceratopsia. In: Weishampel, D.B., Dodson, P., & Osmolska, H. (Eds.). "The Dinosauria" (2nd Edition). Berkeley: University of California Press. Pp. 478-493.
*You H. & Xu X. 2005. An adult specimen of "Hongshanosaurus houi" (Dinosauria: Psittacosauridae) from the Lower Cretaceous of Western Liaoning Province, China. "Acta Geologica Sinica" (English edition) 79(2): 168-173
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