N. Vietnam, Lang Son prov., Huu Lung distr., Huu Lien municipality (N 21°40′ E 106°22′). Primary evergreen broadleaved forest on steep slopes of remnant karst limestone ridge near the top at elev. 250-280 m a.s.l. Lithophytic and terrestrial forb on shady slope. Flowers white.
NTH 3266 02 Oct. 1999
Collectors: N.T. Hiep, N.Q. Binh, L. Averyanov, P. Cribb.