Xiangkhouang Prov., Peak Distr., Khoang village, Pa Khao mt., around point 19°33’02.2’N 103°39’56.3’E. Primary and secondary broad-leaved evergreen dry forest on solid rocky highly eroded limestone at elev. 1200-1450 m a.s.l. Creeping lithophytic vine (10)15 25(35) cm long on open mossy rocks on cliff. Flower bud white. Locally abundant.