Tetracentron
3835025
196973690
2008-03-09T10:19:43Z
Eubot
231599
Removed taxobox colour. See [[User:Eubot/Removing colours from taxoboxen]].
{{Taxobox
| name = ''Tetracentron sinense''
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Dicotyledon|Mangnoliopsida]]
| ordo = [[Trochodendrales]]
| familia = '''Tetracentraceae''' [[Phillippe Édouard Léon van Tieghem|Tiegh.]]
| genus = '''''Tetracentron''''' [[Daniel Oliver|Oliv.]]
| species = '''''T. sinense'''''
| binomial = ''Tetracentron sinense''
| binomial_authority = Oliv.
}}
'''''Tetracentron sinense''''' is a [[flowering plant]], the sole species in the genus '''''Tetracentron'''''. It is also often considered the sole species in the family '''Tetracentraceae''', though some botanists include it in the family [[Trochodendron|Trochodendraceae]] together with the very distinct genus ''[[Trochodendron]]''.
It is native to southern [[China]] and the eastern [[Himalaya]], where it grows at altitudes of 1100-3500 m in a temperate climate; it has no widely used common name in English, though is sometimes called "spur-leaf".
It is a [[tree]] growing to 20-40 m tall. The [[leaf|leaves]] are [[deciduous]] (the ''Flora of China'' reporting it as evergreen is an error), borne singly at the apex of short spur shoots, each leaf dark green, broad heart-shaped, 5-13 cm long and 4-10 cm broad, with a rugose surface and a serrated margin. The spur shoots bear a one leaf each year, slowly lengthening with each subsequent year.
The [[flower]]s are inconspicuous, yellowish green, without petals, produced on slender [[catkin]]s 10-15 cm long; each flower is 1-2 mm diameter. The [[fruit]] is a [[follicle (fruit)|follicle]] 2-5 mm diameter, containing 4-6 [[seed]]s.
''Tetracentron'' shares with ''Trochodendron'' the feature, very unusual in [[flowering plant|angiosperms]], of lacking [[vessel element]]s in its [[wood]]. This has long been considered a very primitive character, resulting in the classification of these two genera in a basal position in the angiosperms; however, genetic research by the [[Angiosperm Phylogeny Group]] has shown it to be in a less basal position (early in the [[eudicot]]s), suggesting the absence of vessel elements is a secondarily evolved character, not a primitive one.
==External links==
*Flora of China: [http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200008490 ''Tetracentron''] and [http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=10877 Tetracentraceae]
*[http://delta-intkey.com/angio/www/tetracen.htm Tetracentraceae] in [http://delta-intkey.com/angio/ L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants.]
*[http://www.biologie.uni-ulm.de/systax/dendrologie/Tetracsin.htm Plant Kaleidoscope: ''Tetracentron'']
*[http://www.ruhr-uni-bochum.de/boga/html/Tetracentron_chinense_Foto.html Ruhr-Universität Bochum: ''Tetracentron'' photos]
[[Category:Plant families]]
[[Category:Trees]]
[[de:Vierspornbaum]]
[[es:Tetracentron]]