关键词: 锦鸡儿属, 分布, 起源

Abstract: The distribution of the genus Caragana is typical Asia Temperature type(Fig. 1), but one species migrated to the subtropical zone of Asia, four to the European and one differentiated in cool Atarctic zone. According the simility of species distribution of caragana, six distribution types were divided, East-Asia type, Middle- Asia type, Mongolia-plateau type, Tibet- plateau type, Black- sea type and Discontined type. Each distribution type have a catalogue (section) dominated. The formation of each type and the relation among the types were discussed. Density map (Fig. 2) show that there are two density centres in the genus Caragana, East- Asia centre and Middle- Asia centre. The former is original centre which has total sections of the genus with 16 species, the latter is variety centre which only have 3 evoluted sections with 15 species. At last, the paper discussed the origin and differentiation of the genus Caragana from Tertiory.

Key words: Caragana, Distribution, Origin