Abstract: | Anacaenaspis yanpingensis sp. nov., from the lower Niuchang Formation (upper Rhuddanian, lower Llandovery, lower Silurian), is the first record of this genus from South China. The biogeographical distribution of Anacaenaspis and some other trilobite genera from South China (e.g., Gaotania, Hyrokybe, Aulacopleura and Raphiophorus) in the Llandovery evidences faunal exchanges between Avalonia–Baltica, Laurentia, Australia and South China. We attribute these dispersals to prevailing ocean currents, and especially equatorial countercurrents, which would have propagated dispersals during the Rhuddanian, shortly after the end-Ordovician mass extinction. |