Three turtle shells from the Middle Jurassic Xintiangou Formation of Yunyang (Chongqing,
China) are described and assigned to Xinjiangchelyidae (Testudines: Eucryptodira).
This is the first report of turtle remains from the Xintiangou Formation, Sichuan
Basin and represents the oldest known Xinjiangchelyidae. The assemblage includes two
taxa, Protoxinjiangchelys sp. and Xinjiangchelyidae indet. This discovery extends
the stratigraphical distribution of Xinjiangchelyidae and improves our knowledge about
the early evolution of that family. It demonstrates that by the Middle Jurassic, at
the time of deposition of the Xintiangou Formation, the group was already diversified
in the Sichuan Basin. (C) 2020 Elsevier Masson SAS. All rights reserved.
