现存被子植物原始类群及其植物地理学研究

On extant primitive angiosperms and their phytogeography

在吸取各学派对被子植物原始类群界定的基础上 ,根据八纲系统 ,提出被子植物原始类群有 60科的新见解 ,并以分子系统学提出的狭义的基部类群 32科为对比 ,进行了植物地理学研究。以科为性状 ,以Takhtajan划分的世界植物区系的“区”为OTU ,UPGMA分析显示 :( 1 )东亚区确是一个十分特殊的区 ,它既与北美东、西部 (北美大西洋区、马德雷区 )有密切关系 ,但更接近印度支那区 ;( 2 )环太平洋的 4个地区集中了较多的原始被子植物的科 ,它们是东亚地区 ,北美东部和西部地区 ,部分热带亚洲、澳大利亚东部和西南太平洋岛屿地区 ,中、南美热带地区。

On the basis of investigating and evaluating the circumscriptions of primitive angiosperms by different authors, in the present paper we proposed a new conception with 60 primitive families of angiosperms following our eight_class system of flowering plants. A phytogeographical study was carried out using these families as characters, and Thakhtajan's floristic “regions” of the world as OTUs. As a contrast, we simultaneously conducted another data set including only 32 basal families according to molecular systematic studies during the recent years. The results by UPGMA analyses indicated that Eastern Asiatic Region is really very unique; it is closely related to North American Atlantic Region and Madrean Region of eastern and western North America, but has more characteristics similar to Indochinese Region. Additionally, the UPGMA trees showed that 4 circum_Pacific districts, e.Asia, e.& w. of N. America, partly tropical Asia, e.Australia, & sw. Pacific islands, tropical C. & S. America, are the areas of great concentration of primitive angiospermous families. This distribution pattern obviously relates to the birthplace and dispersal routes of angiosperms and the history of the Pacific Ocean.