Vietnam, Ha Giang Prov., Bac Me Distr., Phieng Luong Municipality, about 1.5 km to SW of Phieng Luong Municipality headquarter (22º39’29’’N, 105º19’35’’E). Secondary open evergreen broad-leaved forest along rocky streamlet valley at the base of steep slopes of mountains composed with solid highly eroded crystalline and partially shale limestone at elev. about 850 m a.s.l. Climbing shrub. Common.