Vientiane prov., Vang Vieng distr., Oa Hom village, around point 19°06'52.4''N 102°22'35.8''E. Secondary broad-leaved evergreen and semideciduous dry forest with on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. 550-650 m a.s.l. Treelet 4-6 m tall in rather open place on steep rocky slope. Flowers violet. Occasional.