Son La Prov., Moc Chau Distr., Chieng Son comm., Pha Luong village, Pha Luong Mountain (elevation from Pha Luong village at 930 m to Mt. peak at 1860 m a.s.l.). Primary cloud evergreen broad-leaved forest on flat Pha Luong summit composed with eroded red-brown sandstone at elevation 1750-1850 m a.s.l. around point 20°40’23.0N 104°37’52.0E. Lithophytic and terrestrial herb in shady place. Flowers white with blue tint. Common.