The first record of Cretaceous mammaliaform and dinosaur track assemblages from South China

Abstract

Body fossils of Mesozoic mammaliaforms are rare, but their tracks are even rarer. We here describe a probable isolated mammaliaform or tritylodontid track from the Cretaceous of South China. This track is comparable to the ichnotaxa on Chelichnopodidae, and is the first mammaliaform track from South China. The track is a recent discovery at the Huaiji site, which was first described in 2023 and either belongs to the Mawu Formation (Albian–Cenomanian) or the Lailong Formation (Lower Cretaceous), Zhagang Group. Other tracks discovered at the site are described herein, including a theropod track that closely similar to the Grallator morphotype or cf. Asianopodus isp. and two oval impressions that might represent the tracks of a quadruped, possibly a sauropod or a thyreophoran. Currently, the Huaiji site represents the southernmost and most diverse vertebrate ichnofauna in China.