侏罗纪的施迈斯内果(Schmeissneria)是不是被子植物?

中华施迈斯内果在辽西的发现为被子植物的历史添上了重要的一笔。施迈斯内果是一个具有近170年研究历史的植物化石属。新近发现的中华施迈斯内果中发现了以前没被认识到的新特征(未成熟的雌性器官的中央结构有一个纵向的隔壁和封闭的顶端)。新的特征促使人们重新审视该化石的系统位置。王鑫等人通过仔细分析被子植物的定义、结合新的化石特征认为施迈斯内果代表了一个具有被子植物特征的新类群。按照现有的被子植物定义,施迈斯内果可以归入被子植物。这样一来,被子植物的历史就会被前推到早侏罗世。当然也不排除未来被子植物的定义改变后为施迈斯内果建立一个与被子植物平行的种子植物新类群的可能性。文章简要地介绍了施迈斯内果的由来、特征以及王鑫等人如何判定其为被子植物的逻辑思维过程,以便大家论评。

IS JURASSIC SCHMEISSNERIA AN ANGIOSPERM?

The discovery of Schmeissneria sinensis in western Liaoning marks an important record in the study on history of angiosperms. Schmeissneria is a fossil plant genus with an almost 170-year-long history. Recently reported Schmeissneria sinensis demonstrates some new characters previously unrecognized (a longitudinal complete septum and a closed tip in the central unit of the premature female structures). These new characters prompt us to review the affinity of Schmeissneria. Based on a careful examination of the definition of angiosperms and characters of Schmeissneria, Wang et al. concluded that Schmeissneria represents a new taxon with angiospermy. According to the current definition of angiosperms, Schmeissneria may be put in angiosperms. This will push the record of angiosperms back to the earliest Jurassic. However, the possibility of Schmeissneria being a new seed plant group parallel to angiosperms, in case the definition of angiosperms were altered, cannot be excluded completely for the time being. Here we briefly introduce the history of Schmeissneria, its characters and how Wang et al. determined it as an angiosperm.