S.Vietnam, Thua Thien Hue Prov., Phu Loc Distr., Bach Ma National Park, S slope of Bach Ma mt below Hai Vong Dai peak, around point 16°11′11′'N 107°50′57′'E at elev. about 1050 m a.s.l.
Mixed and broad-leaved evergreen dry secondary mt forest on very steep shale/sandstone slopes. Lithophytic herb in crevices of open waterfall cliff. Flowers blue with white base. Common.
HLF 1297 23 April 2003. (Photo).
Coll. L.Averyanov, N.X.Tam, N.T.Vinh. Grant from Henry Luce Foundation.