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''Amentotaxus'' (Catkin-yew) is a genus of conifers comprising five species, treated in either the Cephalotaxaceae, or in the Taxaceae when that family is considered in a broad sense. The genus is endemic to subtropical southeastern Asia, from Taiwan west across southern China to Assam in the eastern Himalaya, and south to Vietnam. The species are evergreen shrubs and small trees reaching 2-15 m tall. The leaves are spirally arranged on the shoots, but twisted at the base to lie in two flat ranks (except on erect leading shoots); they are linear-lanceolate, 4-12 cm long and 6-10 mm broad, soft in texture, with a blunt tip, green above, and with two conspicuous white stomatal bands below. They differ from the related genus ''Cephalotaxus'' in the broader leaves, and from ''Torreya'' by the blunt, not spine-tipped leaves. The species can be either monoecious or dioecious; when monoecious, the male and female cones are often on different branches. The male (pollen) cones are catkin-like, 3-15 cm long, grouped in clusters of 2-6 together produced from a single bud. The female (seed) cones are single or grouped a few together on short stems; minute at first, they mature in about 18 months to a drupe-like structure with the single large nut-like seed 1.5-3 cm long surrounded by a fleshy covering, orange to red at full maturity; the apex of the seed usually protrudes slightly out of the fleshy covering. ==External links== *(Gymnosperm Database ) *(Flora of China ) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Amentotaxus」の詳細全文を読む スポンサード リンク
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