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A new ichnotaxon of fossil bird trac

時(shí)間:2023-04-29 07:00:32 天文地理論文 我要投稿
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A new ichnotaxon of fossil bird track from the Early Cretaceous Tianjialou Formation (Barremian-Albian), Shandong Provin

A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnogenus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (including hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux posteriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much larger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.

作 者: LI Rihui Martin G Lockley LIU MingWei   作者單位: LI Rihui(Qingdao Institute of Marine Geology, China Geological Survey, Qingdao 266071, China)

Martin G Lockley(University of Colorado at Denver, P. O. Box 173364, Denver, Colorado, USA)

LIU MingWei(Fourth Geological and Mineral Resources Survey of Shandong, Weifang 261021, China) 

刊 名: 科學(xué)通報(bào)(英文版)  SCI 英文刊名: CHINESE SCIENCE BULLETIN  年,卷(期): 2005 50(11)  分類號(hào): P5  關(guān)鍵詞: Tetradactyl bird tracks   New ichnogenus Shandongor- nipes   Early Cretaceous   Tianjialou Formation   Shandong Province   China  

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