FLORA OF VIETNAM
Orchidaceae
Bulbophyllum helenae (Kuntze) J.J.Sm.

Tuyen Quang Prov., Na Hang Distr., Sinh Long Municipality, Khuoi Phin village, around point 22°38′21.9″N, 105°20′43.5″E. Primary evergreen mixed humid forest on rocky limestone on highly eroded karstic hills composed with gray solid marble-like limestone at elevation 1100-1200 m a.s.l. Creeping epiphyte. Occasional.
29 September 2013 CPC 5314a
L.Averyanov, N.T.Hiep, L.M.Tuan, N.S.Khang, D.V.Cuong, N.V.Truong.T.Maisak, L.Osinovets
Flowered in May-June 2017. Flowers yellowish. L.Averyanov