An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology
The historically-famous Lotus Fortress site, a deep 1.5–3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.
School of Earth Sciences Resources, China University of Geosciences, Beijing 100083, China;Dinosaur Trackers Research Group, University of Colorado at Denver, Colorado, United States of America;Naturhistorisches Museum Basel, Augustinergasse 2, CH-4001 Basel, Switzerland;School of Earth Sciences Resources, China University of Geosciences, Beijing 100083, China;Institute of Geology and Paleontology, Linyi University, Linyi, Shandong 276000, China;Saurierwelt Paläontologisches Museum, Alte Richt 7, D-92318 Neumarkt, Germany;Peace Region Palaeontology Research Centre, Box 1540, Tumbler Ridge, British Columbia, V0C 2W0, Canada;Peace Region Palaeontology Research Centre, Box 1540, Tumbler Ridge, British Columbia, V0C 2W0, Canada;Museum für Naturkunde, Invalidenstrasse 43, 10115 Berlin, Germany;Departamento de Ciências da Terra (CICEGe-FCT), Universidade Nova de Lisboa, Lisbon 2530−157, Portugal;Moab Giants Tracks Museum, 112 W, SR 313, Moab, Utah, United States of America;Museo del Jurásico de Asturias MUJA (Jurassic Museum of Asturias), Colunga E-33328, Spain;Department of Biological Sciences, University of Alberta 11455 Saskatchewan Drive, Edmonton, Alberta T6G 2E9, Canada;Qijiang District Bureau of Land Resources, Chongqing 401420, China;Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guilin 541004, China;No.208 Hydrogeological and Engineering Geological Team, Chongqing Bureau of Geological and Mineral Resource Exploration and Development, Chongqing 400700, China;Qijiang District Bureau of Land Resources, Chongqing 401420, China
Recommended Citation:
Lida Xing,Martin G. Lockley,Daniel Marty,et al. An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology[J]. PLOS ONE,2015-01-01,10(10)