云南马先蒿属植物的生物地理及物种多样性

Biogeography and Species Diversity of Pedicularis (Scrophulariaceae) of Yunnan

马先蒿属 (Pedicularis)是被子植物中最大的属之一 ,在云南植物区系中占有重要地位。按照钟补求系统 ,该属植物在云南有 15 1种分属于 13个群 72个系。马先蒿属在云南的地理分布体现了下列特点 :(1)种类十分丰富 ,占整个属总种数的 2 5 % ,占中国的 4 2 6 %。(2 )包括了该属全部花冠类型 ,即无齿、有齿的原始类型各为 2 4种、短管具喙的中间过渡类型 87种 ,较进化的长管类型 16种。 (3)马先蒿属植物分布在云南的 11个地理分布区域中 ,但该属植物在康藏高原区最为丰富 ,有 10 8个种在本区有分布 ,占云南种数的 71 5 % ;横断山植物区和东喜马拉雅植物区是本属的现代分布中心和多样化中心。 (4)特有现象十分明显 ,其中 8个系、 5 2个种为云南特有 ,横断山和东喜马拉雅的特有种最为丰富 ,也是本属的特有中心。 (5 )云南马先蒿植物与邻近的四川 (西南部 )和西藏 (东南部 )在区系上联系密切 。

Pedicularis is one of the largest genera of the angiosperms and plays an important role in the flora of the province of Yunnan. Following Tsoong's system, there are 151 species in 72 series of 13 groups (as 'grexes') now recognized within the genus in Yunnan. These represent 64 3% of the series and 100% of the groups of China, respectively. The floristic characteristics of Pedicularis in Yunnan may be summarized as follows: (1) The number of species is rich, constituting 25% of the world's total and 42 6% of the Chinese total. (2) All four corolla types are found within the province, 24 species have toothless corollas, 24 have toothed corollas, 87 species have short tubed, beaked corollas, and 16 species have corollas of the long tubed, beaked type. The intermediate form, i e. the species with short tubed and beaked corollas, is particularly diversified. Almost all major floral evolutionary stages of the genus can be traced in various parts of Yunnan. (3) Although the species of Pedicularis are distributed in all eleven floristic areas. They are most abundant in the Sikang Tibetan subregion, which contains 71 5% of Yunnan's total number of species. It seems clear that the Hengduan Mountains and the East Himalaya Yunnan are the centers of modern distribution and are also the centers of diversification of this genus. (4) There are 8 series and 52 species endemic to Yunnan, which are mostly distributed in the Hengduan Mountains and the East Himalaya. (5) There are some 30 species of Pedicularis common to SE Tibet and Yunnan, and some 61 species common to SW Sichuan and Yunnan,implying close floristic relationships between them. The floristic links between the Pedicularis species of Yunnan and those of Burma and Bhutan are also relatively weak.