Vientiane Prov., Kasi Distr., Thong Mout village, around point 19°26′51.5”N 102°07′45.8”E.
Primary broad-leaved evergreen forest on very steep rocky slopes and on vertical cliffs of remnant highly eroded rocky limestone mountains composed by solid crystalline stratified limestone at elevation 1550-1650 m.
Terrestrial herb 1 m tall along rocky shady stream. Flowers white to light yellowish, median tepal with brightly red spot. Common.