FLORA OF LAOS Orchidaceae Dendrobium gratiosissimum Rchb.f.
Xiangkhouang Prov., Kham Distr., Huad village, Phou tat Vinh mt., around point 19°32′31.6′N 103°39′40.4′E.
Primary and secondary broad-leaved evergreen and semideciduous dry forest on very steep rocky slopes of limestone highly eroded mountains composed by solid marble like limestone at elev. 1200-1400 m a.s.l.
Clustering epiphyte on tall old mossy tree along ridge edge. Flowers white with purple-violet tint, lip with yellow central spot. Common.