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 Climbing terrestrial herb in open wet place along streamlet. Flowers blue-violet. Very common, particularly on secondary open grasslands. HAL 6594 7 March 2005 (Photo).