- dawn redwood
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metasequoia.
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Coniferous, nonevergreen tree (Metasequoia glyptostroboides), the only living species of the genus Metasequoia, of the family Taxodiaceae, native to remote valleys of central China.Both branchlets and leaves grow out in pairs from points along the stem. The bright green, feathery leaves turn reddish brown in autumn. Though Metasequoia fossils are abundant, the tree was thought to be extinct until living specimens were discovered in the 1940s. Only a few thousand are known to have survived, in central China. Since these stands were discovered, seeds and cuttings have been planted throughout the world.* * *
▪ plantgenus of conifers (conifer) represented by a single living species, Metasequoia glyptostroboides, from central China. fossil representatives, such as M. occidentalis, dated to about 90 million years ago during the Late Cretaceous Period, are known throughout the middle and high latitudes of the Northern Hemisphere. Climatic cooling and drying that began about 65.5 million years ago and continued throughout the Cenozoic Era caused the geographic range of the dawn redwood to contract to its present relic distribution. The leaves (leaf) are arranged in pairs on deciduous branchlets, and this deciduous character probably accounts for the tree's abundance in the fossil record. Metasequoia is closely related to the redwood genera of North America, Sequoia and Sequoiadendron.The dawn redwood holds an interesting place in the history of paleobotany as one of the few living plants known first as a fossil. Its fossil foliage and cones (cone) were originally described under the name Sequoia. In 1941, Japanese botanist Miki Shigeru of Osaka University coined the name Metasequoia for fossil foliage with opposite, rather than spirally arranged, leaves. The first living Metasequoia trees were discovered in 1944 by Chinese botanist Wang Zhan in Sichuan province, China. Today, M. glyptostroboides is a common ornamental tree that grows well in temperate climates worldwide.Nan Crystal Arens* * *
Universalium. 2010.