Pollination can be ferocious

 
 
Pollination can be ferocious : 13 posts by 6 authors. 3 images.

Please find some pics shwing pollinators on an Orchid called Bulbophyllum lasiochilum. I have shared few of these pics earlier too, but this time there are two extra images.

It depicts how ferocious act of pollination can be. The pollinator got stuck between the column and labellum and died there itself.

Hope you will find these interesting.

So sad… although this seems to be an accident, this shouldn’t have happened with an orchid 🙁

Yes this is accidental and caused because the insect was not able to release the anther cap and somehow went inside without doing it.

Bulbophyllum has a very peculiar trapping mechanism for pollinators. They have motile labellum and two fang like structures on the column. As the insect moves from the tip of labellum towards inside due to shift in weight the labellum turns upwards and the two fangs clutches the back of insect to hold it. At this point due to movement anther cap is supposed to fall off releasing the pollinia on the back of insect. Once the cap and anther is released, there is enough gap for the insect to come out after minor struggle.
I tried to make some bad sketch sitting on office table to depict this process. Hope it would be understandable.
Fangs are actually stelidia and the length and structure plats important role in identification of species and it also plays important role in deciding which insect can actually be a pollinator.

Thanks … for the nice illustrations and explanation. Very interesting!

The ‘trapping mechanism’ sounds like a carefully selected adaptive feature by some of this most-advanced group of plants.
It also makes me to think that they probably in the process of turning into insectivorous (?), may be in few to several thousand years.
And, they already have achieved a part of that feature (insect trapping mechanism).
Its hard to imagine, but who knows?!

Being insectivorous would technically mean that the plant somehow evolved to produce enzymes like or similar to chitinase that can dissolve outer layer of insects. This is not the case here, The main aim is forced pollination and not killing. If the insects are trapped then its a matter of chance.

I understand it is a clever adaptation to ensure pollination and thus seed-production to continue the legacy… But why trap?

Trap is not to trap insect. Trap is to direct the insect to a right position at right time so pollinia can be stuck to its back. Please remember that the plant is not looking for self pollination. Plant is actually expecting that the insect will carry away the pollinia and pollinate another flower. Most of these Bulbophyllums (not all) are self incompatible.

Got it, thanks. I wonder what reward Bulbophyllums have to offer to their pollinators. Are they looking for any specific type of pollinators, like wasps (?) in this case here, what about honey bees?
I wish I studied pollination biology….

There are glands on the floral parts which secrete oil, resins, wax etc. They are rewarding species.

There is no nectar so no honey bees. Visitors are various kind of flies.