Upper Jurassic conchostracan fossils from central Yunnan and its stratigraphic significance

The authors review the characters, horizons and distribution of various genera in the family Eosestheriopseidae Niu (fam. nov.) and then on that basis they discuss the relationships of this family with the family Eusesthriidae and the origin of the family, depositional break and migration of the family, as well as the evolution of the horizon of its genera such as Chuanjieestheria (gen. nov.), Eosestheriopsis and Yunnanograpta (gen. nov.) in the Upper Jurassic strata of central Yunnan. They first propose that the Shedian Formation/Madishan Formation and Tuodian Formation/Anning Formation might be early Late Jurassic in age, which may be correlated with the Tuchengzi Formation in northern China. The Eosestheriopsis and Pseudograpta faunas are the products of two different biogeographic realms: the Tethyan realm of southern China and the Boreal realm of northern China. These research results have theoretical and practical value for the stratigraphic division and correlation of the continental Jurassic of China and studies of biogeographic realms and their changes and paleotectonics. Some new genera and species of conchostracans.