Amentotaxus

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Amentotaxus
Amentotaxus needles 01.jpg
Fossil Amentotaxus needles
Scientific classification
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Amentotaxus

Species

Amentotaxus argotaenia
Amentotaxus assamica
Amentotaxus formosana
Amentotaxus poilanei
Amentotaxus yunnanensis

Amentotaxus formosana

Amentotaxus is a genus of conifers (catkin-yews) 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 Southeast 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 two to six 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.

Extant Species[edit]

Image Scientific name Common Name Distribution
Amentotaxus argotaenia 2.JPG Amentotaxus argotaenia Catkin yew China: Fujian, southern Gansu, Guangdong, Guangxi, Guizhou, western Hubei, Hunan, Jiangsu, north-western Jiangxi, central and south-eastern Sichuan, south-eastern Tibet and southern Zhejiang
Amentotaxus assamica Assam Catkin yew India
Amentotaxus formosana underside.jpg Amentotaxus formosana Taiwan Catkin Yew Taiwan
Amentotaxus poilanei Poilane's catkin yew Vietnam
Amentotaxus yunnanensis - Lyman Plant House, Smith College - DSC04389.JPG Amentotaxus yunnanensis Yunnan Catkin Yew Laos, Vietnam, and Guizhou and Yunnan in China

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