S.Vietnam, Thua Thien Hue Prov., Phu Loc Distr., Bach Ma National Park, N slope of Bach Ma mt system, to the N-NW of point 16°12′11′'N 107°50′23′'E at elev. 400-600 m a.s.l.
Broad-leaved evergreen wet primary closed forest on very steep sandstone, shale and granite slopes along rocky stream canyon. Terrestrial creeping herb on steep slope. Flower buds pink. Not common.
HLF 1510 30 April - 1 May 2003.
Coll. N.T.Hiep, L.Averyanov, N.T.Vinh et al. Grant from Henry Luce Foundation.