FLORA OF VIETNAM Rubiaceae “Mussaenda with very big seeds”
Border area between Phieng Luong municipality (Ha Giang Prov., Bac Me Distr.) and Sinh Long municipalitiy (Tuen Quang Prov., Na Hang Distr.).
Primary broad-leaved humid evergreen and mixed forest on very steep slopes and along rocky ridge composed with solid crystalline highly eroded limestone at elevation 1100-1170 m a.s.l. around point 22°38′24.3″N 105°20′21.3″E.
Shrub about 3 m tall on slopes and on base of rocky limestone mountain. Fruits black. Common.