Son La Prov., Van Ho Distr., Tan Xuan comm., A Lay village, around point 20°40’46.2N 104°39’49.6E. Primary evergreen broad-leaved forest on very steep rocky slopes and on mountain tops composed with red-brown sandstone at elevation about 1500 m a.s.l. Undershrub 1.5-2 m tall on steep shady slope. Flowers white. Not common.