Quang Binh Prov., Minh Hoa Distr., Hoa Tien municipality, La Van village, around point 17°51′45”N 105°49′45”E.
Highly degraded primary and secondary evergreen broadleaved forest on very steep rocky slopes of remnant limestone hills composed with highly eroded marble-like crystalline limestone at elev. 200-450 m a.s.l.
Herbaceous vine on shelves of high vertical cliff. Flower buds green. Not common.