Vientiane Prov., Vang Vieng Distr., Nathong village, about 5 km to the W of Vang Vieng town, Tham Kang Mt., around point 18°55′51.4”N 102°23′50.6”E. Dry broad-leaved primary and secondary evergreen forest on very steep rocky slopes and on vertical cliffs of remnant highly eroded rocky limestone mountains composed by solid crystalline limestone at elevation 300-500 m. Lithophytic herb in shady place. Leaves rigid, dark uniform green above, very light uniform green below. Not common. LA-VN 375a 14 March 2013 Coll.: N.T.Hiep, L.Averyanov, N.S.Khang, P.V.The, S.Lorphengsy
Flowered under cultivation in September 2013. Flowers pinkish. Averyanov L.