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On the Areal-types of the Chinese Endemic Genera of Seed Plants


The Chinese endemic genera of seed plants, 220 in total, are mainly distributed in China’s tropical and subtropical regions. Among them, 132 genera, including Taiwania, Poliothyrsis, Heptacodium and Shaniodendron, are restricted to eastern and central China. These genera are obviously closely related to eastern Asian elements both floristically and phylogenetically. Seventy-three genera, which mainly occur in southern China, including Hainania, Chunia,  Tetrathyrium, Sinopanax, Allostigma and Gynogyne , actually have extended their ranges to the areas south of the Tropic of Cancer,  and thus reached into the Malaysian Forest Subkingdom of the Palaeotropical Kingdom. They are apparently related to Asian tropical elements. Twelve genera, which occur in western China’s  Qinghai-Xizang plateau, are relatively closely related to central Asian elements. The remaining three genera are endemic to northern China, and related to some degree to temperate Asian elements. The present author considers that the Chinese endemic genera of seed plants are heterogeneous in their origin and development and essentially a mixture of several floristic elements. In the light of their distribution patterns in the two kingdoms, seven subkingdoms and 23 regions in China as proposed by professor C. Y. Wu, the author suggests that the distribution of Chinese endemic genera should be divided into four subtypes: (1) Endemic to eastern and central China (15a); (2) Endemic to southern China(15b); (3) Endemic to western China(15c); (4) Endemic to northern China(15d). Floristically, the endemic genera of the subtype 15b, i. e. those endemic to southern China, are tropical elements, and the endemic genera of subtypes 15a, 15c and 15d are all temperate elements. The above division of the endemic genera of seed plants in China can, in the author’s opinion, better highlight their geographical characteristics, and thus may bring some new light on the analyses of the historical development of the Chinese endemic genera of seed plants.


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