Quang Binh Prov., Minh Hoa Distr., Hoa Son municipality, near B’Lam Lang limestone mt., around point of dipterocarp forest, 17°42′23.8”N 105°47′59”E.
Primary logged closed evergreen broad-leaved forest on silicat valley at elevation about 456 m a.s.l.
Perennial herb, ca. 0.6-0.8 m tall. Old bruits dark violet-brown. Common on stream banks, wet and open. CPC 4393 17 August 2011 Coll.: N.T.Hiep, N.V.Tap, N.S.Khang & L.T.Kien.