title: Hints of the early Jehol Biota: important dinosaur footprint assemblages from the Jurassic-Cretaceous boundary Tuchengzi Formation in Beijing, China.
abstract: New reports of dinosaur tracksites in the Tuchengzi Formation in the newly established Yanqing Global Geopark, Beijing, China, support previous inferences that the track assemblages from this formation are saurischian-dominated. More specifically, the assemblages appear theropod-dominated, with the majority of well-preserved tracks conforming to the Grallator type (sensus lato), thus representing relatively small trackmakers. Such ichnofaunas supplement the skeletal record from this unit that lacks theropods thus far, proving a larger diversity of dinosaur faunas in that region. Sauropods are represented by medium to large sized and narrow and wide-gauge groups, respectively. The latter correspond with earlier discoveries of titanosauriform skeletons in the same unit. Previous records of ornithischian tracks cannot be positively confirmed. Purported occurrences are re-evaluated here, the trackways and imprints, except of a single possible specimen, re-assigned to theropods. Palecologically the Tuchengzi ichnofauna is characteristic of semi-arid fluvio-lacustrine inland basins with Upper Jurassic-Lower Cretaceous deposits in northern China that all show assemblages with abundant theropod and sauropod tracks and minor components of ornithopod, pterosaur and bird tracks.
authors.affiliation: School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
authors.forename: Lida
authors.initials: L
authors.lastname: Xing
authors.affiliation: School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Dinosaur Trackers Research Group, University of Colorado Denver, PO Box 173364, Denver, CO 80217, United States of America.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Lockley
authors.affiliation: Peace Region Palaeontology Research Centre, Box 1540, Tumbler Ridge, British Columbia V0C 2W0, Canada.
authors.forename: Richard T
authors.initials: RT
authors.lastname: McCrea
authors.affiliation: Saurierwelt Paläontologisches Museum, Alte Richt 7, D-92318 Neumarkt, Germany.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Klein
authors.affiliation: Fundación Conjunto Paleontológico de Teruel-Dinópolis, Teruel, Aragón E-44002, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Alcalá
authors.affiliation: Peace Region Palaeontology Research Centre, Box 1540, Tumbler Ridge, British Columbia V0C 2W0, Canada.
authors.forename: Lisa G
authors.initials: LG
authors.lastname: Buckley
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Burns
authors.affiliation: Institute of Evolutionary Biology, University Witten/Herdecke, Stockumerstr. 10-12, 58454 Witten, Germany.
authors.forename: Susanna B
authors.initials: SB
authors.lastname: Kümmell
authors.affiliation: School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: He
mesh_terms: D000818:Animals; D000068476:Beijing; D058448:Biota; D003247:Conservation of Natural Resources; D025061:Dinosaurs; D005528:Foot; D010163:Paleontology