Vietnam, Thua Thien – Hue Prov., Huong Thuy Distr., Duong Hoa Municipality, Huong Thuy forest enterprise territory, around point 16°13'23''N, 107°35'16''E, SW slopes of Mang Chan ridge at elevation about 350-500 m a.s.l. Fractionally logged primary closed evergreen broad-leaved forest along steep stream slopes composed with shale with quartzite. Lithophytic herb on wet shady rocky cliffs along rocky stream canyon. Flowers white with light violet tint. Locally common.