Ha Giang prov., Quan Ba distr., Tung Vai commune, Thang village, around point 23°03ʹ41.5ʺN 104°50ʹ41.6ʺE, steep rocky slopes near mountain top composed with eroded stratified highly eroded limestone at elevation 1200-1400 m a.s.l. Primary evergreen broad-leaved very humid forest. Terrestrial herb 1-1.5 m tall on shady rocks. Flowers buds white. Not rare. 22 April 2018, L. Averyanov, Nguyen Sinh Khang, Nguyen Tien Hiep, Nguyen Quang Hieu, Chuong Quang Ngan, T. Maisak, VR 696 (HN, LE01049621).