FLORA OF VIETNAM Orchidaceae Dendrobium gratiosissimum Rchb.f.
Dien Bien Prov., Muong Cha Distr., Mua Ngai Municipality, around point 21°52′19”N 103°10′01”E.
Remnants of primary evergreen broad-leaved forest on very steep rocky slopes and on tops of remnant mountain composed with highly eroded marble-like solid crystalline limestone at elevation 1150-1250 m a.s.l.
Epiphyte on old mossy trees near top of ridge. Occasional.
CPC 1088d 18 December 2010 Coll.: L.Averyanov, P.K.Loc, P.V.The, N.T.Vinh.
Fl. et coll. under cultivation at 17 March 2011 Flowers odorless; sepals and petals white, purple-violet toward apices; lip white with yellow central spot tinged with greenish, apex purple-violet, boat-like gypochile with dark purple-violet stripes on sides; column white, dark purple-violet at front; operculum pure white, papillose; pollinia yellow; pedicel and ovary light green. L.Averyanov. Photos.