中国麻黄属的地理分布与演化

中国现有麻黄属植物１５种，２变种和１变型，这些种属于膜果麻黄组和麻黄组中的麻黄亚组，没有原始类型藤麻黄亚组的代表。我国除长江中下游及珠江流域的省区处，其他省区都有分布。麻黄花粉的化石－麻分在地层中的分布说明，麻黄在过去曾遍布我国各地，发现的最早时期是在侏罗纪，到白垩纪－早第三纪时，种类较现在丰富，将近５０种，根据麻黄粉在世界各地地层中的分布和时期，结合大陆飘移和海底扩张板块构造学说推断，原麻黄在各

DISTRIBUTION AND EVOLUTION OF THE GENUS EPHEDRA IN CHIA

The genus Ephedra in China includes 15 specics,2 varieties and 1 form belong to Sect.Alatae and Subsect.Ephedra of Sect.Ephedra.These species distribute in all parts of China except for the provinces located in Pearl River valley and median and lower and lower part of Yangtse River valley.The Ephedripites occurred in layers of China show that the genus Ephedra distributed in all parts of China with about 50 species,its earliest appearance in Jurassic and rich in species in Cretaceous and early Tertiary.According to the Ephedripites distribution in the world and the theory of continent driftion and ocean floor spreading-plate tectonics.The process of speciation of primitive species in Ephedra had occurred before the split of the ancient Pangaea. Like the Subsect Scandentes originated form Protoephedra Sect.Alatae are also ancient and has its centre in the deserts of Central Asia.Its secondary centre of species speciation is in Himalaya and Hengduan mountains.