Quang Binh Prov., Minh Hoa Distr., Dan Hoa Municipality, Giang Man Ridge (Vietnam-Laos border) near Cha Lo Vietnam-Lao border gate around point 17°41′50”N 105°45′54”E.
Primary evergreen broad-leaved and coniferous (with Dacrycarpus and Fokienia) wet forest along ridge edge composed with shale and sandstone at elevation about 900-1100 m a.s.l.
Terrestrial undershrub to 1.5 m tall on rocky outcrops. Flowers white with green tint, apex of tube dull purple-violet. Occasional.
HAL 12395 8 February 2009 Coll.: L.Averyanov, P.K.Loc, N.T.Vinh, L.T.Son.