Luang Prabang prov., Pon Xay distr., along the way to Bane Phou Souong village, Pha Hiua Bin Toc Mountain, around point 19°57'37.0''N 102°25'03.0''E. Degraded primary evergreen and semideciduous forest on very steep rocky mountain slopes composed by solid marble like highly eroded limestone at elev. 600-850 m a.s.l. Lithophytic tuberiferous herb in crevices of vertical cliff on mossy rocky mountain top. Leaves velvety dark blue-green above, dark violet below. Rare.