Ha Giang prov., Quan Ba distr., Bat Dai Son Nature Reserve, Thanh Van commune, Mo Sai village, around point 23°07ʹ46.4ʺN 104°57ʹ56.2ʺE, at elevation 1000-1190 m a.s.l., karstic, highly eroded mountains composed of solid marble-like limestone, primary evergreen broad-leaved and mixed (with Pseudotsuga sinensis) humid forest on steep rocky slopes near mountain tops. Shrub 2-3 m tall on rocky mountain slope. Flowers white. Occasional. 18 April 2018, L. Averyanov, Nguyen Sinh Khang, Chuong Quang Ngan, T. Maisak, VR 378 (HN, LE01061496, LE01067048).