Early Devonian chitinozoans from central Guangxi, South China

The latest Silurian to Early Devonian characterises a critical interval in the macroevolution of chitinozoans, marked by a significantly low diversity and the extinction of the entire family Conochitinidae. The South China Block represents one of the classic areas for Devonian research, hosting well-exposed and continuous Pragian successions. However, the Pragian chitinozoans have been poorly investigated, with their biostratigraphical significance remaining to be clarified. This study presents new chitinozoan data from the Lingli section in central Guangxi, South China, where a conodont biostratigraphical framework has been established. A total of four genera and 13 species, including a new taxon, Angochitina tuojiangensis sp. nov., were identified, based on which two global biozones are recognised in ascending order: A. comosa Biozone and A. caeciliae Biozone. Although the chitinozoans from the upper part of the Lingli section have limited biostratigraphical utility, new data from this interval are presented. Additionally, several key chitinozoan species from North Gondwana (e.g., Ramochitina philippoti (Paris)) and eastern Australia (e.g., Angochitina chillkalla Winchester-Seeto) are reported for the first time in the South China Block.