Monday, June 11, 2018

[Botany • 2018] Gastrodia kachinensis (Orchidaceae) • A New Species from Myanmar


Gastrodia kachinensis  X.H.Jin & L.A.Ye

in Aung & Jin, 2018.

Abstract
Gastrodia kachinensis, a new species of Orchidaceae, is described and illustrated from Putao, Kachin State, Myanmar. It is morphologically similar to G. gracilis, presumably its nearest relative, but can be easily distinguished from the latter by having perianth tube with punctate outer surface, verrucose outer surface of sepal lobe, orbicular petals, ovate-elliptic lip with truncate apex and auriculate-clawed base, glabrous lip apex with a pair of twin protuberance-like lamellae and column with a pair of blade-like lateral wings and acute stelidia at apex. Identification key and colour photographs are provided. A preliminary risk-of-extinction assessment, according to the IUCN Red List Categories and Criteria, is given for the new species.

Keywords: Gastrodieae, Kachin, key, montane forest, taxonomy


Figure 3. Gastrodia kachinensis X.H.Jin & L.A.Ye.
A Inflorescence B Longitudinal section of sepal tube, showing two petals C Front view of column and lip, showing the stigma area with sectile pollinia D Sepal tube, lip, lateral view of column and the base of lip, showing a pair of sub-globose calli at lip hypochile E Rhizome. Photographed by X.H. Jin.

Figure 2. Habit of Gastrodia kachinensis.
Photographed by X.H. Jin. 

Figure 1. Gastrodia kachinensis X.H.Jin & L.A.Ye.
A Rhizome B Inflorescence C Longitudinal section of sepal tube, showing two petals D Front view of column and lip, showing the stigma area with sectile pollinia E Lateral view of column and hypochile, showing a pair of sub-globose calli at lip hypochile F Lip epichile, showing a pair of twin protuberance-like lamellae at its apex. Illustration by Yunxi Zhu. 

Gastrodia kachinensis X.H.Jin & L.A.Ye

Diagnosis: Gastrodia kachinensis is similar to G. gracilis, but it can be easily distinguished from the latter by having perianth tube with punctate outer surface, verrucose outer surface of sepal lobe, orbicular petals, ovate-elliptic lip with truncate apex and auriculate-clawed base, glabrous lip with a pair of twin protuberance-like lamellae only at apex and column with a pair of blade-like lateral wings and acute stelidia at apex.

....

Etymology: The new species is named after Kachin State, the northernmost state of Myanmar in which it was discovered in a vast area of primitive montane forest.

Distribution and habitat: Gastrodia kachinensis is a terrestrial mycoheterotrophic species that grows in broad-leaved, evergreen forest at 1400 m in elevation. Gastrodia kachinensis is only known from the type locality.


Ye Lwin Aung and Xiao-Hua Jin. 2018. Gastrodia kachinensis (Orchidaceae), A New Species from Myanmar. PhytoKeys. 94; 23-29.  DOI: 10.3897/phytokeys.94.21348