Vietnam, Quang Binh Prov., Minh Hoa Distr., Dan Hoa municipality, Chuong Lon mountain, Vietnam-Laotian border, about 6 km to N of Cha Lo borders station, around point 17°44′04″N 105°46′53″E.
Primary broad-leaved forest on very steep slopes and rocky cliffs of remnant mountain composed with solid marble-like highly eroded limestone at elevation 400-700 m a.s.l.
Treelet to 3 m tall on top of mountain. Flowers white. Not rare.
HAL 11691 19 April 2008 Coll.: L.Averyanov, P.K.Loc, N.T.Vinh, N.S.Khang