N. Vietnam, prov. Lai Chau, distr. Sin Ho, municipality Ta Ngau about 30 km of Lai Chau town to the N (N 22°18′ E 103°15′). Secondary open wet mossy evergreen broadleaved forest with remnants of primary elements on rocky steep slope of remnant karst limestone ridge at elev. about 1650 m. Adpressed lithophyte forb on shady vertical cliffs. Flowers deep blue. Common.
NTH 2793 25 May 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)