Quercus langbianensis
Quercus langbianensis is the accepted name of an uncommon oak tree species in the Asian sub-genus of Cyclobalanopsis in the family Fagaceae.[2] 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 forests of Cambodia, China (mostly Yunnan)[3] and Vietnam.
| Quercus langbianensis | |
|---|---|
| Scientific classification  | |
| Kingdom: | Plantae | 
| Clade: | Tracheophytes | 
| Clade: | Angiosperms | 
| Clade: | Eudicots | 
| Clade: | Rosids | 
| Order: | Fagales | 
| Family: | Fagaceae | 
| Genus: | Quercus | 
| Subgenus: | Quercus subg. Cyclobalanopsis | 
| Species: | Q. langbianensis | 
| Binomial name | |
| Quercus langbianensis Hickel & A.Camus 1921 | |
| Synonyms[1] | |
| Cyclobalanopsis camusiae  (Trel. ex Hickel & A.Camus) Y.C.Hsu & H.Wei Jen | |
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 and tomentose when young, less hairy with age.[3]
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
    
 Data related to Quercus langbianensis at Wikispecies Data related to Quercus langbianensis at Wikispecies
- Line drawings, Flora of China Illustrations vol. 4, fig. 378, drawing 5-11 at lower left
 Media related to Quercus at Wikimedia Commons Media related to Quercus at Wikimedia Commons