N. Vietnam, Ha Giang prov., Yen Minh distr., Lao Va Chai municipality, vicinities of Lao Va Chai village (N 23°07′ E 105°08′), 35.9 km to 27° of Ha Giang city. Primary wet evergreen broadleaved closed forest on very steep slope of karst remnant limestone ridge at 1200 m alt. Shrublet up to 1 m hg on open mossy rocks. Flowers white with smallest purple-violet marks up down. Not common.
NTH 3469 09 Oct. 1999
Collectors: N.T. Hiep, N.Q. Binh, L. Averyanov, P. Cribb.