A preliminary report on two new vertebrate track sites including dinosaurs from the Early Cretaceous Hekou Group, Gansu Province, China

摘要: Two track sites were discovered in the Hekou Group(Early Cretaceous), Yanguoxia, Yongjing County, Gansu Province, China. More than 108 dinosaur and pterosaur trackways occur on same gray fine sandstone surface of two sites. Site 1 (600 ㎡) contains 245 dinosaur, 25 pterosaur, 4bird tracks. A total 1,392 tracks with one are preserved 2 (1,000 ㎡). Dinosaur attributable to theropods, sauropods, ornithopods both One theropod site consists an unusual didactyl footprints, suggestive a dromaeosaurid such as Deinonychus. Unusual sauropod ornithopod also found at sites, which appear have been made by swimming sauropods shallow water. These include that tail-drag marks between left right footprints. trackway represents first record footprints China, six pairs manus pes isolated impression. This is from Early Cretaceous Asia. comprehensive analysis tracksites deduced overlapping sequences indicates sedimentary environment changed gradually terrestrial into lacustrine condition. The co-occurrence bird shows unique faunal association this area