Houphan Prov., Viengxay Distr., Vieng Xai village, around point 20°23'41.3''N 104°13'44.5''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. 800-950 m a.s.l.
Creeping epiphytic and lithophytic vine 2-3 m long. Spathe greenish, inflorescence yellow. Locally common.