摘要
With the verification of the type specimen by six experts from the Nanjing Institute of Geology and Palaeontology, the specimen of Xianfengella prima He and Yang, 1982 described by Qian （Qian, 2001, flge2： la-c） is confirmed to be the holotype specimen （NIGP. 84430） of Yangtzedonta primitiva Yu, 1985, and consequently, Yu Wen＇s view that they are not the same specimen is impractical. This fact demonstrates that Yangtzedonta primitiva Yu, 1985 is undoubtedly a junior synonym of Xianftngella prima He and Yang, 1982, and is invalid. Qian＇s conclusion （Qian, 2001 ） that no bivalve appeared in the early Meishucunian Stage of the Early Cambrian is rational.
With the verification of the type specimen by six experts from the Nanjing Institute of Geology and Palaeontology, the specimen of Xianfengella prima He and Yang, 1982 described by Qian （Qian, 2001, flge2： la-c） is confirmed to be the holotype specimen （NIGP. 84430） of Yangtzedonta primitiva Yu, 1985, and consequently, Yu Wen＇s view that they are not the same specimen is impractical. This fact demonstrates that Yangtzedonta primitiva Yu, 1985 is undoubtedly a junior synonym of Xianftngella prima He and Yang, 1982, and is invalid. Qian＇s conclusion （Qian, 2001 ） that no bivalve appeared in the early Meishucunian Stage of the Early Cambrian is rational.
基金
This work was supported by the Major State Basic Research Project(Grant No.G200007 7700)
the National Natural Science Foundation of China(Grant Nos.40572006 and 40232020).
