Pseudotaxus Genus (white-berry yew)

1 Species

Pseudotaxus, as decribed in 1947 by Wan-chun Cheng in Research Notes, Forestry Institute; National Central University, Nanking, China, is commonly known as White-berry or White-cup yew; as well as 白豆杉 ( báidòushān [ literally "white bean conifer" ]) in the Chinese language. White-berry yew is a mono-specific genus of conifer in the Taxaceae family and as such, is closely related to the other yews in the genus Taxus.

The genus name comes from the Greek and Latin languages meaning "false yew." The difference in mature aril color is the major distinction between this conifer and true yews (Taxus spp.). The sole extant species of Pseudotaxus, P. chienii, was originally described as a species of Taxus (Taxus chienii W.C. Cheng in 1934). 13 years later, it was nearly simultaneously independently split out to a previously unrecognized new genus by both W.C. Cheng and Carl Florin (as Nothotaxus, 1948). Cheng's study was earlier by 3 months. DNA studies confirm both the similarities and differences from other Taxaceae genera. Taxus and Pseudotaxus are considered sister genera, but the closest genetic relative to the White-berry yew is the distinctive New Caledonian yew (Austrotaxus).

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Description. Like other yews, white-berry yew is a small coniferous shrub or small tree, reaching mature heights of 6 to 15 feet (2 - 5 m) tall with reddish bark and a broadly domed crown. It is dioecious, with the male and female cones on different trees.

  • The leaves are lanceolate and flat, measuring 0.4 to 1.12 inch (1 - 2.6 cm) long and 0.08 to 0.12 inch (2 - 3 mm) broad, colored dark green above, with two white stomatal bands below. They are arranged spirally on the stem, but with the leaf bases twisted to align the leaves in two flat rows on either side of the stem. The conspicuous white stomatal bands on the harder, stiffer (less soft) leaves readily distinguish it from the yews in the genus Taxus.
  • The seed cones (female fruiting bodies) are very similar to those of Taxus species, but the aril is white when mature, not red. They measure 0.2 to 0.28 inch (5 - 7 mm) long and wide.
  • The pollen cones (male fruiting bodies) have a globose shape, and measure 0.12 to 0.16 inch (3 - 4 mm) in diameter.

Distribution. This genus is native to southern China — occurring in northern Guangdong, northern Guangxi, Hunan, Southwest Jiangxi and southern Zhejiang provinces. It is grown as an ornamental plant in southern China, but almost never elsewhere. There are also no known selected cultivars.

Attribution from: Wikipedia

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