''Thuja sutchuenensis'', the Sichuan thuja, is a species of ''

Thuja ''Thuja'' ( ) is a genus of coniferous tree or shrub in the Cupressaceae (cypress family). There are five species in the genus, two native to North America and three native to eastern Asia. The genus is monophyletic and sister to ''Thujopsis''. M ...

'', an

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

coniferous

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

in the cypress family Cupressaceae. It is native to China, where it is an endangered local

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

Chengkou County Chengkou County () is a county in Chongqing municipality, China, and is the northernmost county-level division of Chongqing, bordering the provinces of Shaanxi and Sichuan to the north and west, respectively. To the northeast, the county borders ...

( Chongqing Municipality, formerly part of

Sichuan Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...

province), on the southern slope of the

Daba Mountains The Daba Mountains, also known by their Chinese name as the Dabashan, are a mountain range in Central China between the watersheds of the Yellow and Yangtze Rivers. Part of the larger Qinling mountain range, it cuts through four provinces: Si ...

Description

It is a small or medium-sized tree, reaching possibly 20 m tall, though no trees of this size are currently known. The foliage forms in flat sprays with scale-like leaves 1.5–4 mm long, green above, and with narrow white stomatal bands below. The

cones A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines conn ...

are oval, green ripening brown, 5–8 mm long and 3-4.2 mm broad (opening to 7 mm broad), with 8-10 overlapping scales.

Discovery and rediscovery

It was first described in 1899 from specimens collected by the French botanist

Paul Guillaume Farges Father Paul Guillaume Farges (1844–1912) was a French Catholic missionary, botanist and plant collector, based for much of his life (from 1867) in China, serving at Chongqing from 1892 until his death. He collected over 4,000 plant specimens, ...

in 1892 and 1900, but was not seen again thereafter, despite many searches, for almost 100 years and was presumed to be extinct due to over-cutting for its valuable scented

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin ...

. A small number of specimens were however rediscovered in 1999, growing on very inaccessible steep ridges close to (or at the same site) where Farges had first found it. The area of its occurrence has now been designated a Special Protection Area in order to protect the species.

References

External links

* {{Taxonbar, from=Q1969504 sutchuenensis Endemic flora of China Flora of Sichuan Trees of China Endangered flora of Asia