Vientiane prov., Kasi distr., Si Sang Vone village, around point 19°06′10.9′'N 102°10′46.1′'E.
Secondary and primary evergreen dry forest on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. 600-750 m a.s.l.
Undershrub 1.5-2 m tall in rather open place on rocky steep slope. Flowers light violet. Common.