Son La Prov., Van Ho Distr., Chieng Xuan Municipality, Co Hong village, territory of Xuan Nha natural reserve, Pha Luong Mountain.
Primary coniferous forest with Pinus cernua on very steep mountain slopes and cliffs composed by brown sandstone at elevation 1000-1050 m a.s.l. around point 20°42′14.2″N 104°43′53.9″E.
Herbaceous vine to 3 m long among short gnarled trees on very steep open mossy slopes and cliffs. Occasional.