A Conspectus and Phytogeography of the Genus Carex Subgen. Vignea (P. Beauv.) Kirsch. in China
中国苔草属二柱苔草亚属的系统总览及植物地理学的研究

In spite of different views on the classification of the genus Carex, the su- bgenus Vignea (P. Beauv.) Kirsch. in it is relatively natural subgroup adopted by most mo- dern caricologists. The total number of species in this subgenus is about 330, particularly abun- dant in the subarctic and temperate regions of the Northern Hemisphere. (Fig. 1. Tab. 1.). The conspectus of Chinese subgenus Vignea, consisting of 48 species, 7 subspecies and 1 variety, is given in this article. These 54 taxa (with species, subspecies and variety treated equally at the same rank and with one widely distributed species and one uncertain species excluded for floristic analysis here) can be grouped into 4 types of floristic elements according to the floristic regions of the world suggested by Takhtajan (1986). 1. The elements of the Circumboreal Region (Fig. 2.): Carex diandra, C. vulpina, C. stipata, C. otrubae, C. curaica, C. disperma, C. bohemica, C. angustior, C. loliacea, C. tenui- flora and C. lachenalii. They constitute 20.4% of the total and are principally distributed in the Eurasian Forest Subkingdom of China. Wu's scheme (1979) for the Chinese floristic division is adopted here. 2. The elements of the Eastern Asiatic Region (Figs. 3, 4, 5): Carex echinochloaeformis, C. enervis subsp. chuanxibeiensis, C. rochebruni subsp. remotispicula, C. ovatispiculata, C. neu- rocarpa, C. nubigena subsp. pseudo-arenicola, C. nubigena subsp. albata, C. paxii, C. leiorhyn- chya, C. laevissima, C. pseudocuraica, C. pallida, C. yamatsutana, C. lithophyla, C. kobomugi, C. gibba, C. remotiuscula, C. rocheruni subsp. rochebruni, C. rochebruni subsp. reptans, C. alta, C. maackii, C. omiana, C. pallida var. angustifolia, C. earistata, C. thompsonii, C. larice- torum, C. maorshanica, C. dailingensis, C. unisexualis C. heilongjingensis. They constitute 55.5% of the total taxa. Wu (1979) considers that the Eastern Asiatic Region is better divid- ed into the Sino-Himalayan Forest Subkingdom and the Sino-Japan Forest Subkingdom. Among the taxa mentioned above, only the first four species occur in the Sino-Himalayan Forest Sub- kingdom and the remaining ones are of the Sino-Japanese Forest Subkingdom. In fact, the elements of the Sino-Japanese Forest Subkingdom constitute 48.1% of the total, obviously higher than in the other regions. Moreover, of these taxa the latter eight are endemic to Sino- Japanese Subkingdom and constitute 61.5% of the endemics of China. It comes to a conclusion that speciation of Chinese subgenus Vignea is more rapid here than elsewhere. 3. The elements of the Irano-Turanian Region (Fig. 6.): Carex duriuscula subsp, durius- cula, C. duriuscula subsp, rigescens, C. duriuscula subsp, stenophylloides, C. reptabunda, C. pycnostachya, C. enervis, C. pseudofoetida, C. sagaensis and C. physodes. They constitute 16.7% of the total and are mainly distributed in Asiatic Desert Subkingdom, Eurasian Steppe Subkingdom and Qing