Cao Bang Prov., Bao Lac Distr., Hong An municipality, Mi Lung village.
Primary broad-leaved and mixed humid evergreen forest on very steep slopes and along rocky ridge composed with solid crystalline highly eroded limestone at elevation 1500-1550 m a.s.l. around point 22°50′01.3″N 105°50′05.7″E.
Lithophytic scandent herb to 1.5 m tall on very steep mossy rocky slope and cliffs near mountain tops. Flowers yellow. Common.