N.Vietnam, Ha Tinh Prov., Huong Son Distr., Son Kim Municipality, Rao Bun stream around point 18°23′39′'N, 105°15′12′'E. Primary broad-leaved evergreen closed wet forest on very steep shale slopes of river canyon at elevation about 300 m a.s.l.
Prostrate herb in crevices of open stream rocks. Flowers white. Common.