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.
Remnants of primary evergreen broad-leaved forest along rocky stream valley composed with shale and sandstone at elevation about 320 m a.s.l.
Shrub of treelet to 3 m tall. Flowers white to light pink-purple along wet stream rocks in rather open place. Common.
HAL 12287 5 February 2009 Coll.: L.Averyanov, P.K.Loc, N.T.Vinh, L.T.Son.