Middle Devonian ostracods from Jiwozhai patch reef(Dushan, Guizhou Province, South China):Biostratigraphic and palaeoecological implication

The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.