A coalition of American and Chinesepaleontologists, including Xu Xing, Catherine Forster, Jim Clark, and Mo Jinyou, described and named Yinlong in 2006. The generic name is derived from the Mandarin Chinese words 隱 (yǐn: "hidden") and 龍 (lóng: "dragon"), a reference to the movie Crouching Tiger, Hidden Dragon, large portions of which were filmed in the western Chinese province of Xinjiang, near the locality where this animal's fossil remains were discovered. Long is the word most often used in the Chinese media when referring to dinosaurs. The species was named after the American vertebrate paleontologist William Randall Downs III, a frequent participant in paleontological expeditions to China who died the year before Yinlong was discovered.[1]
The known fossil material of Yinlong consists of many skeletons and skulls.[2] The first specimen discovered was a single exceptionally well-preserved skeleton, complete with skull, of a nearly adult animal, found in 2004 in the Middle-Late Jurassic strata of the Shishugou Formation located in Xinjiang Province, China. Yinlong was discovered in an upper section of this formation which dates to the Oxfordian stage of the Late Jurassic, or 161.2 to 155.7 million years ago.[1][2] Most other described ceratopsians are known from the later Cretaceous Period.
Descriptionedit
Life reconstruction of Y. downsi
Yinlong was a relatively small dinosaur, reaching 1.2 m (3.9 ft) in length and 10 kg (22 lb) in body mass.[3] Despite a virtually frill-less and totally hornless skull, Yinlong is a ceratopsian. Its skull is deep and wide and relatively large compared to most ornithischians, but also proportionately smaller than most other ceratopsians. Long robust hindlimbs and shorter slender forelimbs with three-fingered hands suggests a bipedal lifestyle like many small ornithopods.[1][3]
Classificationedit
A small rostral bone on the end of the upper jaw clearly identifies Yinlong as a ceratopsian, although the skull displays several features, especially the ornamentation of the squamosal bone of the skull roof, which were previously thought to be unique to pachycephalosaurians. The presence of these features in Yinlong indicates these as actual synapomorphies (unique features) of the larger group Marginocephalia, which contains both the pachycephalosaurs and the ceratopsians, although these features have been lost in all known ceratopsians more derived than Yinlong.[1] The addition of these characters further strengthens the support for Marginocephalia. Yinlong also preserves skull features reminiscent of the family Heterodontosauridae, providing support for the hypothesis that heterodontosaurids are closely related to marginocephalians[4][5][6] The group containing Marginocephalia and Heterodontosauridae has been named Heterodontosauriformes. However, this hypothesis was not supported by a subsequent analysis of basal ornithischians that was carried out as part of a study on the postcranial anatomy of Yinlong, which resolved the below phylogeny of Ceratopsia.[7]
Yinlong was discovered with seven gastroliths preserved in the abdominal cavity. Gastroliths, stones stored in the digestive tract and used to grind plant material, are also found in other ceratopsians such as Psittacosaurus, and are also widely distributed in most other dinosaur groups, including birds.[1]
^ abcdefXu, X., Forster, C.A., Clark, J.M., and Mo, J. (2006). "A basal ceratopsian with transitional features from the Late Jurassic of northwestern China." Proceedings of the Royal Society B: Biological Sciences, 273(1598): 2135-2140. doi:10.1098/rspb.2006.3566
^ abcHoltz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix.
^ abPaul, Gregory S. (2016). The Princeton Field Guide to Dinosaurs. Princeton University Press. p. 271. ISBN978-1-78684-190-2. OCLC 985402380.
^Zhao X., Cheng Z., & Xu X. 1999. "The earliest ceratopsian from the Tuchengzi Formation of Liaoning, China." Journal of Vertebrate Paleontology 19(4): 681-691.
^Cooper, M.R. 1985. "A revision of the ornithischian dinosaur Kangnasaurus coetzeei Haughton, with a classification of the Ornithischia." Annals of the South African Museum 95: 281-317.
^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: 15–20.
^Fenglu Han; Catherine A. Forster; Xing Xu; James M. Clark (2017). "Postcranial anatomy of Yinlong downsi (Dinosauria: Ceratopsia) from the Upper Jurassic Shishugou Formation of China and the phylogeny of basal ornithischians". Journal of Systematic Palaeontology. 16 (14): 1159–1187. doi:10.1080/14772019.2017.1369185. S2CID 90051025.
External linksedit
Wikimedia Commons has media related to Yinlong.
GW News Center, featuring a link to the original paper, pictures, and a press release on the discovery of Yinlong (site operated by George Washington University)
March 13, 2024
yinlong, simplified, chinese, 隐龙, traditional, chinese, 隱龍, pinyin, yǐn, lóng, meaning, hidden, dragon, genus, basal, ceratopsian, dinosaur, from, late, jurassic, period, central, asia, small, primarily, bipedal, herbivore, temporal, range, late, jurassic, pre. Yinlong simplified Chinese 隐龙 traditional Chinese 隱龍 pinyin yǐn long meaning hidden dragon is a genus of basal ceratopsian dinosaur from the Late Jurassic Period of central Asia It was a small primarily bipedal herbivore 1 2 YinlongTemporal range Late Jurassic 158 Ma PreꞒ Ꞓ O S D C P T J K Pg N Fossil skullScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClade DinosauriaClade OrnithischiaClade CeratopsiaFamily ChaoyangsauridaeGenus YinlongXu et al 2006Species Y downsiBinomial name Yinlong downsiXu et al 2006 Contents 1 Discovery and species 2 Description 3 Classification 4 Diet 5 See also 6 References 7 External linksDiscovery and species editA coalition of American and Chinese paleontologists including Xu Xing Catherine Forster Jim Clark and Mo Jinyou described and named Yinlong in 2006 The generic name is derived from the Mandarin Chinese words 隱 yǐn hidden and 龍 long dragon a reference to the movie Crouching Tiger Hidden Dragon large portions of which were filmed in the western Chinese province of Xinjiang near the locality where this animal s fossil remains were discovered Long is the word most often used in the Chinese media when referring to dinosaurs The species was named after the American vertebrate paleontologist William Randall Downs III a frequent participant in paleontological expeditions to China who died the year before Yinlong was discovered 1 The known fossil material of Yinlong consists of many skeletons and skulls 2 The first specimen discovered was a single exceptionally well preserved skeleton complete with skull of a nearly adult animal found in 2004 in the Middle Late Jurassic strata of the Shishugou Formation located in Xinjiang Province China Yinlong was discovered in an upper section of this formation which dates to the Oxfordian stage of the Late Jurassic or 161 2 to 155 7 million years ago 1 2 Most other described ceratopsians are known from the later Cretaceous Period Description edit nbsp Life reconstruction of Y downsiYinlong was a relatively small dinosaur reaching 1 2 m 3 9 ft in length and 10 kg 22 lb in body mass 3 Despite a virtually frill less and totally hornless skull Yinlong is a ceratopsian Its skull is deep and wide and relatively large compared to most ornithischians but also proportionately smaller than most other ceratopsians Long robust hindlimbs and shorter slender forelimbs with three fingered hands suggests a bipedal lifestyle like many small ornithopods 1 3 Classification editA small rostral bone on the end of the upper jaw clearly identifies Yinlong as a ceratopsian although the skull displays several features especially the ornamentation of the squamosal bone of the skull roof which were previously thought to be unique to pachycephalosaurians The presence of these features in Yinlong indicates these as actual synapomorphies unique features of the larger group Marginocephalia which contains both the pachycephalosaurs and the ceratopsians although these features have been lost in all known ceratopsians more derived than Yinlong 1 The addition of these characters further strengthens the support for Marginocephalia Yinlong also preserves skull features reminiscent of the family Heterodontosauridae providing support for the hypothesis that heterodontosaurids are closely related to marginocephalians 4 5 6 The group containing Marginocephalia and Heterodontosauridae has been named Heterodontosauriformes However this hypothesis was not supported by a subsequent analysis of basal ornithischians that was carried out as part of a study on the postcranial anatomy of Yinlong which resolved the below phylogeny of Ceratopsia 7 nbsp Restoration of Yinlong hiding from two GuanlongCeratopsia AlbalophosaurusPsittacosaurus lujiatunensisPsittacosaurus mongoliensisChaoyangsauridae Stenopelix valdensisYinlong downsiChaoyangsaurus youngiXuanhuaceratops nieiHualianceratops wucaiwanensisNeoceratopsia Liaoceratops yanzigouensisArchaeoceratops oshimaiKoreaceratops hwaseongensisYamaceratops dorngobiensisAquilops americanusAuroraceratops rugosusMosaiceratops azumaiLeptoceratops gracilisBagaceratops rozhdestvenskyiProtoceratops andrewsiDiet editYinlong was discovered with seven gastroliths preserved in the abdominal cavity Gastroliths stones stored in the digestive tract and used to grind plant material are also found in other ceratopsians such as Psittacosaurus and are also widely distributed in most other dinosaur groups including birds 1 See also editTimeline of ceratopsian researchReferences edit a b c d e f Xu X Forster C A Clark J M and Mo J 2006 A basal ceratopsian with transitional features from the Late Jurassic of northwestern China Proceedings of the Royal Society B Biological Sciences 273 1598 2135 2140 doi 10 1098 rspb 2006 3566 a b c Holtz Thomas R Jr 2011 Dinosaurs The Most Complete Up to Date Encyclopedia for Dinosaur Lovers of All Ages Winter 2010 Appendix a b Paul Gregory S 2016 The Princeton Field Guide to Dinosaurs Princeton University Press p 271 ISBN 978 1 78684 190 2 OCLC 985402380 Zhao X Cheng Z amp Xu X 1999 The earliest ceratopsian from the Tuchengzi Formation of Liaoning China Journal of Vertebrate Paleontology 19 4 681 691 Cooper M R 1985 A revision of the ornithischian dinosaur Kangnasaurus coetzeei Haughton with a classification of the Ornithischia Annals of the South African Museum 95 281 317 You H Xu X amp 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 15 20 Fenglu Han Catherine A Forster Xing Xu James M Clark 2017 Postcranial anatomy of Yinlong downsi Dinosauria Ceratopsia from the Upper Jurassic Shishugou Formation of China and the phylogeny of basal ornithischians Journal of Systematic Palaeontology 16 14 1159 1187 doi 10 1080 14772019 2017 1369185 S2CID 90051025 External links edit nbsp Wikimedia Commons has media related to Yinlong GW News Center featuring a link to the original paper pictures and a press release on the discovery of Yinlong site operated by George Washington University Retrieved from https en wikipedia org w index php title Yinlong amp oldid 1206170097, wikipedia, wiki, book, books, library,
