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.
Creeping lithophytic and epiphytic vine. Spathe dull light brown-yellow, flowers white. Very common. Co-dominant of herbaceous lithophytic communities on lower and middle part of mountain slopes.