N. Vietnam, Thai Nguyen prov., Vo Nhai distr., Than Sa municipality, vicinities of Kim Son village (N 21°48′ E 105°54′), 23.3 km to 18° of Thai Nguyen city. Shrub about 3 m hg on open rocks of limestone cliffs along stream at 40-60 m a.s.l. Flowers white, anthers purple-violet, calyx reddish-purple. Not common.