Vientiane prov., Kasi distr., between San and Tham Tai villages, around point 19°17'47.9''N 102°08'58.9''E.
Secondary broad-leaved evergreen dry forest on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. 900-1000 m a.s.l.
Lithophytic herb on vertical shady cliff. Leaves from glaucous-green to dull purple-violet. Locally common.