摘要
本文依据八角科的系统分类和地理分布，结合古植物、古地理和古气候资料，分析和推论八角科的起源地点在劳亚古陆，很可能是在劳亚古陆中南部的温暖湿润山地。八角科的起源时间早于白垩纪末期，很可能在白垩纪中期。八角科的迁移扩散途径是沿山地进行，从西欧进入北美，从北往南，从内陆往沿海。世界现代八角科植物是以东亚成分为主，东亚的横断山至华东一带（２０—３０°Ｎ，９８—１２３°Ｅ）为八角科的现代分布中心、现代分化中心和东亚八角科现代原始类群分布中心。八角科曾为古热带湿润山地分布型，现代为东亚－北美分布型；现代分布格局形成的原因在欧美是因为海浸和冰川作用，在亚洲则是寒化（冰川）和旱化的综合作用，而物种丰富程度则是由于东亚较北美有更多的地理隔障机制。
Illiciaceae,comprising one genus and 34 species,is an E.Asia & N.America disjunctive distribution family.Following Takhtajan' s floristic regions of the world,the number of species in each region are counted.The statistics show that the regions in richness of number of species can be arranged in order sequence as:Eastern Asiatic Region(24 species,71% of total number of species in the family),Indochinese Region(9,26%),Malesian Region(7,21%),Caribbean Region(2,6%)and Atlantic-Northern American Region(2, 6%).According to the evidence of distribution and systematics of the family,and combining with the material of palaeobotany,palaeogeography and palaeoclimatology, it can be concluded as follows:(1)Illiciaceae was originated in Laurasia before late Cretaceous,and might be originated on the warm and wet mountains in the Midsouth of Laurasia during middle Cretaceous.(2)Its dispersal ways were along mountains from W.Europe to N.American,from north to south and from continental to coastland.(3)The centre of modern distribution and differentiation of the family is in the area from Hengduashan to E.China(20-30°N,98-123°E).This area is also the distribution centre of primitive species of E.Asia.(4)The family distributed in palaeotropical mountains before Neogene.But at the present time,it is disjunctive between E.Asia and N.America.The reasons why leaded to the pattern of modem distribution were caused by the action of transgression and glacier in Europe and N.America,and were caused by the action of glacier and aridity in Asia.(5)There are much more species in Asia than in N.America,because the geology in Asia is more complicated than in N.America.
出处
《热带亚热带植物学报》
CAS
CSCD
1995年第3期1-11,共11页
Journal of Tropical and Subtropical Botany
基金
国家自然科学基金
中国科学院生物分类区系特别支持
华南植物研究所所长基金
关键词
八角科
地理分布
起源
Illiciaceae
Distribution
Origin
