Luang Prabang prov., Pon Xay distr., between Houay Man and Nam Bo villages, Phou Hua Ben Toc Mountain, around point 19°57'33.1''N 102°25'25.8''E.
Degraded primary evergreen and semideciduous forest on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. 500-650 m a.s.l.
Woody wine to 10 m long on open mossy rocks on mountain tops. Flowers light pink with bright red nerves. Occasional.