Vietnam, Quang Binh Prov., Minh Hoa Distr., Thuong Hoa Municipality, about 2 km to E of Ban On village (17є40'21''N, 105є58'00E). Heavily logged primary and secondary closed evergreen broad-leaved forest and scrub on rocky ridge composed with solid and stratified marble-like highly eroded crystalline limestone at elevation 550-650 m a.s.l.
Lithophytic herb on very steep rocky slope. Flowers light violet. Common.