Laos, Khammoune prov., Boualapha distr., Ban Dou village, around Khuay cave, at 17°30′35.1″N, 105°51′28.7″E.
Primary dry evergreen and semideciduous broad-leaved forest on very steep rocky slope near karstic hill top composed with solid, marble-like highly eroded limestone at 250-390 m a.s.l.
Erect terrestrial and lithophytic herb, later herbaceous or semi-woody vine on rocky slope. Flowers white to light yellowish, corona pale brownish-pink. Not common.