Vientiane prov., Vang Vieng distr., Patang village, around point 19°04'15.6''N 102°24'33.2''E. Secondary broad-leaved semi-deciduous dry forest on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. about 670 m a.s.l. Terrestrial undershrub to 2 m tall. Flowers white. Not rare.