N. Vietnam, Son La prov., Moc Chau distr., Long Luong municipality, near Sang Cai village (20°45′51′'N, 104°51′26′'E). Primary wet broad-leaved evergreen and semideciduous mossy forest along remnant limestone highly eroded ridge at elev. 1300-1450 m a.s.l. Creeping herb in open grassy place. Flowers odorless. Tepals white with violet tint toward tips, central petal purple-violet with white stripes. Very common.