Vietnam, Nghe An Prov., Tuong Duong Distr., Tam Quang Municipality, Tung Huong village, along Khe Mat stream around point 19°03′09″N 104°36′53″E at elevation about 355 m a.s.l.
Lowland closed secondary old evergreen forest on steep slopes along rocky stream valley composed with stratified solid shale and sandstone.
Terrestrial herb in rather open place. Flower buds white. Not rare.
HLF 6756 19 March 2007.
Coll. Averyanov L., P.K.Loc, N.V.Trai, N.T.Vinh, N.D.Phuong, Averyanova A. Grant from Henry Luce Foundation.