关于"扬子蛤属是先锋贝属无疑"的质疑

2005年,地质学报(英文版,79卷第6期)同时刊出了余汶、钱逸关于扬子蛤(Yangtzedonta)与先锋贝(Xianfengella)是否为同一化石的争论文章.这一争论由来已久.引起多方关注.笔者详细观察了保存于中国科学院南京地质古生物研究所标本馆的余汶(1985)的Yangtzedonta primitiva Yu正模标本(标本登记号84430号)和钱逸(2001)的 Xian fengella等模标本(登记号125018-125022),认为84430号标本是一枚发育有特殊后接合缘构造、形态较为奇特的小壳化石.尽管饯逸(2001)称拥有与84430号标本相似的"更多、更精美的同类标本"和"完整个体",但他不仅从未展示具有与84430号标本相似后接合缘等形态构造的图影,还以与实际形态不相符的失真素描图等不实依据,混淆了84430号标本与Xianfengella在形态构造和壳体大小等方面的真实区别,断言84430号标本是一块Xianfengella的破碎标本,坚称"扬子蛤属是先锋贝属无疑"(地质学报(英文版),79卷第6期第777页).对此,笔者提出质疑.

"Yangtzedonta is Undoubtedly a Junior Synonym of Xianfengella" is to be Queried

In 2005,the Acta Geologica Sinica(in English edition,vol.79,no.6) contemporaneously issued two articles respectively by Yu Wen and Qian Yi on the topic of whether Yangtzedonta and Xianfengella are synonymous or not.The topic has long been debated and caused a wide concern as well.By examining in detail the holotype specimen of Yangtzedonta primitiva Yu by Yu Wen in 1985 with the Cat.no.84430,and the specimen of Xianfengella described by Qian Yi in 2001 with the Cat.no.125018~125022,the both stored in the Nanjing Institute of Geology and Palaeontology,the Chinese Academy of Sciences.The close observation suggests that the holotype specimen of Yangtzedonta primitiva Yu,1985 with Cat.no.84430 is a small shelly fossil with unique morphological characteristic and developed with peculiar posterior hinge structure.Although Qian Yi announced that more well preserved specimens in analogous with the holotype specimen of Yangtzedonta primitiva Yu with Cat.no.84430 and complete shell are at his disposal,he has never illustrated any of his specimens with similar posterior hinge structure as seen in the holotype of Yangtzedonta primitiva Yu.Indeed,he has confused the real differences in the morphological characteristics and the size of shell between the holotype of Yangtzedonta primitiva Yu and Xianfengella by illustrating a sketch drawing which is neither the original nor the real morphological characteristics.Therefore the author has to raise a query to the conclusion made by Qian as "Yangtzedonta is undoubtedly a junior synonym of Xianfengella" and "the holotype of Yangtzedonta primitiva Yu,1985 which is just the cracked and contorted specimen of Xianfengella prima described by Qian."