Quang Binh Prov., Minh Hoa Distr., Thuong Hoa municipality, around point 17°41′19”N 105°53′35.5”E.
Primary closed evergreen broad-leaved forest on higher part of remnant mountain rocky slope composed with solid highly eroded crystalline limestone at elevation about 566 m a.s.l.
Terretrial herb to 1.2 m tall. On shady slope. Leaves bright green beneath. Flower buds yellowish. Not rare.