Phu Tho Prov., Tan Son Distr., Xuan Son Municipality, Du village, Nhon Mountain, around mountain top, point 21°06’51”N 104°57’34”E. Remnants of primary evergreen primary forest on very steep slopes and cliffs composed with solid highly eroded marble-like limestone at elevation about 600 m a.s.l. Creeping epiphyte and lithophyte on mossy rocky top of mountain. Locally very common. Co- and mono-dominant of herbaceous mountain top cover.
HAL 12829b 19 February 2009
Coll.: L.Averyanov, P.K.Loc, N.T.Vinh, L.T.Son.
Fl. in November 2013. Flowers white, sepal tips yellowish. Photo. A.Schirokov