Bulbophyllum blepharistes Rchb.f., Flora 55: 278 (1872).

Distribution: Burma, Thailand, Vietnam and Laos

Section tripudianthes.

When G.Seidenfaden & T.Smitinand made notes on this species in 'The Orchids of Thailand' 1961 they made the following observations.

"At the point of attachment of the lip, is a glossy, globular, deep yellow gland, evidently having a function at pollination. When th lip is touched near it's base it will suddenly snap upwards, pressing a visiting insect towards the column, the lip moving back to it's horizontal position in less than a minute, whereupon the operation can be repeated".

I have tried to simulate this action over several years and I have never seen this phenomenon.
My own observations and comments are. The flowers are presented in the horizontal position. The lateral sepals are connate along their lower edge and form a concave depression which is filled with a sticky sugary secretion,(shown in the picture) below the base of the lip. There are short upcurved sidelobes at the base of the lip. When an insect alights on the lip, which is very mobile it is tipped towards the column. The sidelobes at the base of the lip act as paddles in the thick secretion and offer resistence to the trapped insect trying to free itself. Eventually of course (after a struggle and depending on size) a very tired insect emerges.
bernabu