FLORA OF VIETNAM
Orchidaceae
Paphiopedilum helenae Aver.

N.Vietnam, Bac Kan Prov., Na Ri Distr., Liem Thuy Municipality, village Lung Vai, around point 21°57′18′'N, 106°06′12′'E, at elevation 500-700 m a.s.l. Primary broad-leaved evergreen closed wet forest on very steep slopes and cliffs of rocky ridges and mesae composed with white solid marble-like crystalline limestone. Lithophytic herb on vertical shady cliff. Occasional.
HAL 4981 28 May 2004
Collectors: L.Averyanov, N.T.Hiep, P.V.The, N.T.Vinh.