Son La Prov., Thuan Chau Distr., Muoi Noi Municipality, Sang village, around point 21°18′28”N 103°48′33”E.
Remnants of primary broadleaved evergreen forest on top of remnant mountain composed with solid highly eroded limestone at elevation 1000-1100 m a.s.l.
Epiphyte on mossy tree in shady place. Flowers light green. Common.
CPC 1811 30 March 2011 Photos. Coll.: L.Averyanov, N.T.Hiep, T.B.Ngan.