N.Vietnam, Bac Kan Prov., Cho Don Distr., Ban Thi Municipality, village Phia Khao, Lung Li valley, around point 22°16′10′'N, 105°31′01′'E, Cot Moc mountain at elevation 800-900 m a.s.l.
Primary broad-leaved evergreen closed forest on very steep slopes and cliffs near tops of rocky ridge composed with solid marble-like stratified limestone.
Treelet 3-4 m tall on wet mossy cliff. Flowers light pink. Common. Co-dominant on tops of ridge at 900-1000 m a.s.l.