N Vietnam, Ha Giang Prov., Quan Ba Distr., Can Ty Municipality, Tia Sung Valley, Bat Dai Son Natural Reserve around the point 23°05'79 N, 105°01'01 E. Primary closed evergreen dry broad-leaved and coniferous forest on steep slopes and on tops of remnant limestone mountains at elev. of 1220 m a.s.l.