N.Vietnam, Ha Tinh Prov., Huong Son Distr., Son Hong Municipality, around point 18є34'06''N, 105є11'40''E. Heavily logged primary broad-leaved evergreen dry forest on steep mt slopes composed with shale at elev about 250-350 m a.s.l. along Song Con river valley. Treelet 2-3 m tall. Flowers yellowish-green. Common.