The discovery of middle Yunnan genus Chuanjieestheria(Conchostraca) in the Houcheng Formation of northern Hebei Province and its geological significance

The conchostracan fossils, such as Chuanjieestheria Niu, Eosestheriopsis Shen et Chen, and Yunnanograpta Niu were oring-inally collected from Upper Jurassic Madishan Formation, Anning Formation and Tuodian Formation in central Yunnan Province.Af-ter that, these fossils were found from Upper Jurassic Shuining Formation and Penglaizhen Formation in Sichuan Basin.In 1980, ge-nus Chuanjieestheria Niu was found in Yanjiagou Village, Xuanhua City, Hebei Province by the authors.The discovery of this genus is of important significance in the stratigraphic division and correlation.