Taxaceae
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Taxaceae
The family Taxaceae, commonly called the yew family, includes three genera and about 7 to 12 species of coniferous plants, or in other interpretations (see Classification, below), six genera and about 30 species. They are much branched, small trees and shrubs. The leaves are evergreen, spirally arranged, often twisted at the base to appear 2-ranked. They are linear to lanceolate, and have pale green or white stomatal bands on the undersides. The plants are dioecious, rarely monoecious. The male cones are 2-5 mm long, and shed pollen in the early spring. The female cones are highly reduced, with just one ovuliferous scale and one seed. As the seed matures, the ovuliferous scale develops into a fleshy aril partly enclosing the seed. The mature aril is brightly coloured, soft, juicy and sweet, and is eaten by birds which then disperse the hard seed undamaged in their droppings. Classification
Phylogeny of the Taxaceae and Cephalotaxaceae - note that both groups have evolved from within the other conifers The genera Torreya and Amentotaxus, previously included in this family, are better transferred to the Cephalotaxaceae, as genetic tests show they are more closely related to Cephalotaxus than to Taxus. Alternatively, they may be included, with Cephalotaxus, in a broader interpretation of Taxaceae as a single larger family (Price, 2003). In this sense, the Taxaceae includes six genera and about 30 species. The differences between the Taxaceae and the Cephalotaxaceae are as follows:
* To 25 mm in Austrotaxus A few botanists have transferred Austrotaxus to its own family, the Austrotaxaceae, suggesting it may be closer to the Podocarpaceae than to the other Taxaceae, but genetic evidence does not support this transfer. References
bg:?????? ca:Taxàcia da:Taks-familien de:Eibengewächse es:Taxaceae eo:Taksusacoj fr:Taxaceae ko:??? io:Taxuso it:Taxaceae lv:?vju dzimta lt:Kukmediniai hu:Tiszafafélék nl:Taxusfamilie no:Barlindfamilien pl:Cisowate pt:Taxaceae fi:Marjakuusikasvit vi:H? Thanh tùng tr:Porsukgiller Source: Wikipedia | The above article is available under the GNU FDL. | Edit this article
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