FLORA OF VIETNAM Rubiaceae Uncaria macrophylla Wall.
N.Vietnam, Thanh Hoa Prov., Ba Thuoc Distr., Co Lung Municipality, Eo Dieu village, around point 20°25′56′'N, 105°14′12′'E. Primary evergreen seasonal broad-leaved closed lowland forest on crystalline marble-like highly eroded limestone, very steep rocky mt slopes at elev. 500-600 m. Climbing shrub or woody vine 8-12 m lg in open place. Flowers yellowish-white, fragrant. Common.