Middle to Late Ordovician (late Darriwilian to early Sandbian) ostracods from the Meitan area of northern Guizhou, SW China

Abstract

Well-preserved ostracods are documented for the first time from the upper Shihtzupu Formation (late Darriwilian to early Sandbian) of northern Guizhou Province, SW China. A total of 10 species are identified, including Pilla reedi (Wolfart, 2001a), Laccochilina (Prochilina) yanpingensis sp. nov., Ulrichia chekiangensis? Hou, 1956, Euprimitia compta Sun, 1987, Aechmina sp., Quadritia sp., Longiscula? sp. 1, Longiscula? sp. 2, Longiscula? sp. 3 and Silenis? sp., with the first two most common. Such an ostracod assemblage shows some similarities to ostracods documented from the Miaopo Formation of the same age in the Yichang area, Hubei Province, southern China, as well as to contemporaneous faunas found in Baltica, Australia, India, Sibumasu and the Argentine Precordillera. A global review of the temporal and spatial distribution of the biogeographically significant genus Pilla suggests that it might have originated in low-latitude areas and then migrated to other peri-Gondwana terranes like South China during the Ordovician. Yichi Zhang [zhangyc@nigpas.ac.cn], School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, PR China; State Key Laboratory of Palaeobiology and Stratigraphy, Center for Excellence in Life and Palaeoenvironment, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China.