Vietnam, Lang Son Prov., Bac Son Distr., Tan Tri Municipality, around Na Mau village. Highly degraded primary and secondary broad-leaved evergreen forest on very steep slopes and along tops of ridge composed with solid highly eroded crystalline gray marble-like limestone at elevation about 500-600 m a.s.l. Tree 5-8 m tall on top of ridge. Flowers red-purple. Very common. Usual co-dominant of the forest.
Record creation: 2026-10-19, Аверьянов Леонид ВладимировичCitation: Specimen LE 01360720 // Virtual herbarium of Komarov Botanical Institute RAS — http://re.herbariumle.ru/01360720