Quang Tri Prov., Huong Hoa Distr., Huong Viet municipality around point 16°51′06”N 106°34′38”E.
Partially destroyed primary broadleaved evergreen forest on very steep rocky slopes of remnant hills composed with solid highly eroded crystalline limestone at elev. about 600-700 m a.s.l.
Woody vine to 10 m long on shady rocky slope. Flowers brightly red, anther dull yellow. Not common.