Vietnam, Ha Giang Prov., Bac Me Distr., Phieng Luong Municipality, about 1.5 km to SW of Phieng Luong Municipality headquarter (22°39′29″N, 105°19′35″E).
Fractionally logged primary closed evergreen broad-leaved forest on slopes of streamlet in lower part of slopes of mountains composed with solid highly eroded crystalline limestone at elev. about 850-1000 m a.s.l.
Climbing terrestrial herb in open wet place along streamlet. Flowers blue-violet. Very common, particularly on secondary open grasslands.