Ha Giang prov., Quan Ba distr., Tung Vai commune, Thang village, around point 23°03ʹ13.4ʺN 104°51ʹ48.8ʺE, steep rocky slopes of stream valley composed with eroded stratified highly eroded limestone at elevation 1000-1200 m a.s.l. Primary evergreen broad-leaved very humid forest. Densely clustering herb on open wet mossy river rocks. Flowers white. Locally common. 23 April 2018, L. Averyanov, Nguyen Sinh Khang, Nguyen Tien Hiep, Nguyen Quang Hieu, Chuong Quang Ngan, T. Maisak, VR 761 (HN, LE01050106).