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 old mossy tree on rocky top of mountain. Not common.
CPC 1818c 30 March 2011 Coll.: L.Averyanov, N.T.Hiep, T.B.Ngan.
Fl. under cultivation in Sep. 2012. Flowers dirty violet, apical part of lateral sepals turning yellowish. Averyanov L. Photos.