Lower Devonian Lycophytes from Sichuan and the Paleogeographic Context of Coeval Plant Assemblages from South China

Premise of research. Devonian assemblages from South China have become an important source of data on the rise of land plants and are thus supplementary to a scenario historically based on fossils from the Laurussian region and Siberia. Less attention has been given to assemblages from Sichuan and their paleogeographic significance than to those from Yunnan and adjacent provinces in China.Methodology. Descriptions of plants, including lycopsids, with enations are based on coalified compression fossils lacking anatomy, and they complete our analyses of the Sichuan Lower Devonian assemblages. Compiled species lists for the entire assemblage are compared with those from coeval assemblages from South China using simple statistical methods (including Simpson's coefficient of similarity).Pivotal results. Studies confirm the presence of endemic lycophytes and emphasize the importance of detailed study of Drepanophycus spinaeformis before any conclusions about its global occurrence can be made.Conclusions. Statistical analysis of the whole flora confirms that the assemblage from Sichuan is distinct from that at Yunnan, but distinguishing two further subregions in South China requires descriptions of further taxa.