云南临沧晚中新世槭属叶片和翅果研究

云南省是研究我国植物多样性,植物区系演化及被子植物迁徙路线的有利场所。文中鉴定并描述了采自云南临沧上中新统邦卖组的槭属(Acer)8块叶片和17块翅果化石,共鉴定为4个种,其中包括1个新种和1个相似种,分别为Acer lincangense sp.nov.和Acer cf.jingdongense。槭属化石在云南邦卖组的出现,证明了该植物群具有北温带和古热带的混生特征,反映了当时植物区系类型的多样化构成了云南现代植物多样性的基础。另外,通过对Acer全球大化石记录以及现生种的统计,总结得出槭属的地史演化具有3个发展高峰期:依次为始新世、中新世和全新世,从古至今呈现一种螺旋式递增趋势。

Acer Leaves and Samaras from the Late Miocene of Lincang,Yunnan Province

Yunnan Province is a favorable place for investigation of plants diversity, floristic evolution and migration routes of angiosperms. In this study, eight leaf impressions and seventeen winged fruits ofAcer from the upper Miocene Bangmai Formation of Lincang, Yunnan Province were investigated. They are assigned into four species, including one new species-Acer lincangense sp. nov. and one conformis-Acer cf. jingdongense. The occurrence of the genus Acer in the Bangmai Formation provides the evidence that the Lincang flora was mixed with elements of the north temperate and paleotropical zones. And this character of Neogene floristic diversity formed the basis of modern plant diversity in Yunnan Province. Furthermore, on the basis of statistical analysis of the number of fossil species at different geological periods and extant species at present, the evolutionary history of the diversity of Acer can be divided into three optimum phases, i.e., the Eocene, the Miocene and the post-Holocene. The diversity of Acer at species level is spirally increased through the three evolutionary cycles.