Vientiane Prov., Kasi Distr., Thong Mout village, around point 19°25′19.7”N 102°08′32.7”E.
Primary broad-leaved evergreen forest on very steep slopes and on cliffs of remnant mountain composed with solid crystalline highly eroded limestone at elevation about 1550 m.
Terrestrial herb to 1.5 m tall on open alluvial slope among secondary shrubs. Flowers bluish. Common.