S.Vietnam, Thua Thien Hue Prov., Xuan Loc Distr., Bach Ma National Park, along Dong Truoi ridge and S slopes around point 16°14′11′'N 107°44′28′'E.
Broad-leaved evergreen primary closed forest on very steep granite slope at elev. 800-900 m a.s.l. Lithophytic semishrub 0.3-0.5 m tall on shady waterfall side cliff. Flower buds dull dirty violet. Locally common.
HLF 1728 7 May 2003.
Coll. N.T.Hiep, L.Averyanov, N.T.Vinh et al. Grant from Henry Luce Foundation.