Son La Prov., Van Ho Distr., Xuan Nha Municipality, Pu Lau village, territory of Xuan Nha natural reserve. Remnants of primary and secondary broad-leaved evergreen dry forest on cliffs and on very steep slopes of remnant hill composed by highly eroded stratified dark gray shale limestone at elevation 500-700 m a.s.l. around point 20°40’35.4’’N 104°48’14.3’’E. Lithophytic rosulate herb on shady cliffs, particularly on travertine deposits near mountain top. Flowers blue. Common.