''Quercus langbianensis'' is the accepted name of an uncommon oak tree species in the Asian sub-genus of ''
Cyclobalanopsis
An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ...
'' in the family
Fagaceae.
These differ from other ''Quercus'' subgenera in that they have
acorns with distinctive cups: usually with substantial rings, made-up of scales that have grown together. This species can be found in sub-tropical and
tropical seasonal forest
Seasonal tropical forest, also known as moist deciduous, semi-evergreen seasonal, tropical mixed or monsoon forests, typically contain a range of tree species: only some of which drop some or all of their leaves during the dry season. This tropic ...
s of
Cambodia
Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailan ...
, China (mostly
Yunnan
Yunnan , () is a landlocked province in the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is Kunming. The province borders the C ...
)
[Flora of China, ''Cyclobalanopsis camusiae'' (Trelease ex Hickel & A. Camus) Y. C. Hsu & H. W. Jen, 1993. 法斗青冈 fa dou qing gang ]
/ref> and Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
.
Description
''Quercus langbianensis'' is an evergreen tree that reaches a height of up to 15 m. The bark is rough, with spots. The branches are brown an
tomentose
when young, less hairy with age.[
The leaves measure 70-140 (up to 170) x 25–40 mm, elliptical-lanceolate to oblanceolate, leathery and glabrous on both sides, with margins having numerous small teeth that are obtuse, wavy near the apex: which is acuminate to slightly caudate; petioles are 15–20 mm and hairless.
The acorns are sub-globose approximately 17–20 mm, covered with fine silky hair (sericeous), pale brown and ripening by September; scars are approximately 10 mm in diameter and convex. Their styles are persistent about 2 mm in diameter. Superficially, the cups are bowl-shaped, 8 x 20–25 mm approximately, enclosing 1/2 or 2/3 of the acorn. Outside and inside the reddish]
tomentose
acorn has a wall about 3 mm thick. The bracts are formed by 5 to 7 rings, with whole margins.
References
External links
*
Line drawings, Flora of China Illustrations vol. 4, fig. 378, drawing 5-11 at lower left
*
{{Taxonbar, from=Q15338425
langbianensis
Trees of Cambodia
Trees of Vietnam
Flora of Indo-China
Plants described in 1921
Taxa named by Aimée Antoinette Camus