Houphan Prov., Viengxay Distr., Xieng Luong village, around point 20°22′06.1′'N 104°17′18.6′'E.
Primary and secondary broad-leaved evergreen dry forest on very steep rocky slopes of highly eroded mountains composed by solid marble-like limestone at elev. 600-700 m a.s.l.
Woody vine 3-4 m long in secondary shrubs on alluvial foothill slope of limestone mountain. Occasional.