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.
Fl. in cult. in January 2015. Flowers odorless, sepals and petals brownish with purple tint, median sepal and petals – darker; lip brown-red, side lobes dark brown-purple to almost black; column and operculum yellowish, column at front on side margins – dark purple. Photos. 27 Jan 2015, L.Averyanov