Vietnam, Thua Thien – Hue Prov., A Luoi Distr., Huong Nguyen Municipality, about 8 km to the N of Tra Ve forest protection station, around point 16°17′17′'N, 107°26′40′'E at elevation about 240 m a.s.l.
Secondary closed evergreen broad-leaved forest on steep hill and mountain slopes composed with shale along stream valley.
Terrestrial herb up to 2.5 m tall. Flowers light dull blue in open places. Very common. Co- and mono-dominant of secondary communities in open slopes.