Cirsium boninense

Cirsium boninense is a species of thistle in the family Asteraceae that is endemic to the Bonin Islands of Tōkyō Metropolis, Japan.

Taxonomy
The species was first described by Japanese botanist Gen-ichi Koidzumi in 1914. The specific epithet relates to the type locality (Chichijima) in the Bonin Islands.

Description
Cirsium boninense is a perennial plant with white flowers from May to June that grows to a height of 40 - 150 cm among the grasses and rocks in coastal areas, as well as on the forest floor.

Conservation status
Cirsium boninense is classed as Near Threatened on the Ministry of the Environment Red List. According to the Red Data Book Tokyo, though decreasing on Chichijima, numbers are increasing on Muko-jima and Nakōdo-jima.