Theropod tracks from the Upper Jurassic Dongxing formation Dongxing city and an overview of dinosaur assemblages from Guangxi, China

Guangxi Zhuang Autonomous Region is an important region for dinosaur fossil discoveries in southern China, but its Jurassic dinosaur record remains relatively sparse. In 2021, dinosaur tracks were first discovered in Nanmushan Village, Dongxing City, which is currently the southernmost known dinosaur fossil record in China. The Nanmushan track site preserved at least seven theropod tracks. The morphotype A is tentatively assigned to cf. Chongqingpus , which belongs to the Eubrontes morphotype tracks. Morphotype B is more poorly preserved, but indicates the presence of larger theropods in the region. This study also reviews the stratigraphic sequences of the Jurassic-Cretaceous deposits in Guangxi, identifying 14 tetrapod fossil sites from the Jurassic to the Cretaceous. Regional comparison of the dinosaur assemblages reveals a high degree of similarity between the Middle-Upper Jurassic dinosaur fauna of Guangxi and that of the Sichuan Basin. The early Cretaceous faunal assemblage of the Xinlong Formation is very similar to that of northeastern Thailand, suggesting the possible existence of a distinct “southern” zoogeographical region in southern China and Southeast Asia. This research provides new evidence for the reconstruction of the Mesozoic dinosaur diversity and palaeoecological patterns in the Guangxi region. • A detailed description of the Late Jurassic theropod tracks in Dongxing. • The Dongxing dinosaur trackmakers include at least two types. • The similarities of the Jurassic dinosaur faunas of the Guangxi and Sichuan basin. • A southern zoogeographical region existed in southern China and Southeast Asia in K1.