Son La Prov., Van Ho Distr., Tan Xuan Municipality, Cot Moc village, territory of Xuan Nha natural reserve, eastern slopes of Pha Luong Mountain.
Remnants of primary and secondary broad-leaved evergreen humid forest on very steep mountain slopes composed by shale and sandstone at elevation about 900-1450 m a.s.l. around point 20°40’33.3’’N 104°39’00.3’’E.
Lithophytic herb on large mossy stream boulders along narrow shady rocky stream canyon. Flowers pink, anthers and stigmas yellow. Common.