A new ichnotaxon of fossil bird track from the Early Cretaceous Tianjialou Formation (Barremian- Albian), Shandong Province, China

作     者：LIRihui MartinGLockley LIUMingwei 

作者机构：QingdaoInstituteofMarineGeologyChinaGeologicalSurveyQingdao266071China UniversityofColoradoatDenverEO.Box173364DenverColoradoUSA FourthGeologicalandMineralResourcesSurveyofShandongWeifang261021China 

出 版 物：《Chinese Science Bulletin》 (Chin. Sci. Bull.)

年 卷 期：2005年第50卷第11期

页      面：1149-1154页

核心收录：

学科分类：070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 

基　　金：National Key Project of Geoscience Surveys, (200211000001) National Natural Science Foundation of China, NSFC, (40172008) Natural Science Foundation of Shandong Province 

主　　题：四趾鸟类足迹 鸟类化石 白垩纪时代 中国 山东 

摘      要：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 ichnoge- nus 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 (in- cluding hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux pos- teriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much lar- ger 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.