N. Vietnam, Tuyen Quang prov., Na Hang distr., Thanh Tuong municipality, near Ban Bung village (22°16′26′'N, 105°25′58′'E). Primary broad-leaved evergreen very dry forest (with Burettiodendron hsienmu as a main dominant) near top of limestone ridge at elev. about 600 m a.s.l. Tree 6-8 m hg on very steep rocky slope composed with slaty stratified limestone. Very common. Codominante of 2 forest stratum. HAL 171 21 March 2001