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 300-400 m.
Tree 6-10 m tall in open place along stream. Flowers yellow with purple. Not rare.