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). Heavily logged primary closed evergreen broad-leaved forest on slopes and tops of mountains composed with solid highly eroded crystalline limestone at elev. about 900-1150 m a.s.l. Lithophytic and epiphytic creeping succulent vine up to 10 m long. Flower buds light greenish. Locally common.