Species Diversification of Genus Cirsium (Asteraceae) in Japan

다국어 초록 (Multilingual Abstract)

Genus Cirsium (Asteraceae) from Japan is revised based on both field and herbarium examinations. As a result it is clarified that the Cirsium flora of Japan is consisted of more than 120 species and that several groups are considerably diversified in the Japanese Archipelagoes. Here two instances will be shown for the diversification. The northern maritime group (sect. Onotrophe subsect. Littoralicola), a recently recognized group, is differentiated in the maritime regions of Honshu and Hokkaido. The Cirsium kagamontanum group (sect. Onotrophe subsect. Reflexae), the most diversified group in Japan, is differentiated mainly in the cool temperate zone of Honshu and Shikoku.