Son La Prov., Yen Chau Distr., Muong Lum Municipality, Na Vang village around point 21°01′19”N 104°30′45”E.
Primary coniferous mixed forest with Calocedrus rupestris on very steep rocky slopes of remnant mountain composed with highly eroded solid limestone at elevation 900-1100 m a.s.l.
Terrestrial herb on shady slope. Flowers odorless, tepals light violet, lip white with violet tint and yellow spot on epichile. Rare.
CPC 1898 2 April 2011 Photos. Coll.: L.Averyanov, N.T.Hiep, T.B.Ngan.