Quang Binh Prov., Tuyen Hoa Distr., Lam Hoa municipality, Hung village, around point 17°55′41”N 105°49′43”E.
Highly degraded primary and secondary evergreen broadleaved forest on very steep rocky slopes of remnant limestone hills composed with highly eroded marble-like crystalline limestone at elev. 200-300 m a.s.l.
Lithophytic herb to 1.5 m tall in humid wet depression between limestone hills. Flowers white. Abundant.