Orchid Pollination
Broad Lipped Twayblade [Neottia convallarioides]. Coos County, N.H. 7-12-15. Notice the Fungus Gnat [a known pollinator for this plant]
Known pollinators of Purple Fringeless Orchid [Platanthera peramoena]. Spicebush Swallowtail Butterfly [Papilio troilus] and Hummingbird Clearwing Moth [Hemaris thysbe]. Also pictured pollinia stuck on the stigma and unknown pollinator hairs stuck in the stigmatic fluid.
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The Incredible story of the pollination of the Ragged Fringed Orchid [Platanthera lacera] How this orchid evolved to form partnerships with moths for the continuation of its species is truly remarkable.The different strategy story of the pollination of the Ragged Fringed Orchid [Platanthera lacera]. Looking at the first picture you can see the orifice opening to the spur is bisected [a pallet] into two distinct openings, compared to the spur opening for the Platanthera ciliaris [last picture] which is round and not bisected [no pallet]. The insect, in the case of P. lacera a moth [Unspotted Cooper Moth [Allagrapha aerea] is a known pollinator], drawn in by fragrance is forced to one the side or the other to place it's proboscis deep into the spur to get it's sweet reward of nectar. In doing so it's tongue [proboscis] comes into contact with the viscidium and pulls out the pollinarium. The dual openings helps guide the the proboscis to one side or the other and closer to the pollinarium and better insuring of one getting attached to the proboscis by the sticky viscidium. This is in contrast to P. ciliaris, which uses a Butterfly [Spicebush Swallowtail [Papilio troilus] is a known pollinator], After leaving the inflorescence [flower] can have one or both pollinarium attached to it's eye[s]. Having dual openings to the spur [nectary] in Platanthera species that places the pollinarium on the tongue of the pollinator is common and is another ingenious way of insuring pollination in orchids. Southeast, Pa.
A Spicebush Swallowtail [Papilio troilus] Butterfly in the act of pollinating Platanthera ciliars. You can see, attached to the eye pollinarium, which it has unknowingly removed from the flower. The pollinarium, the male part of the flower, contains the pollinia which will hopefully brush up against and come into contact with the stigma [the female part of the flower]. When the butterfly flies to the next inflorescence [flower], the one or two pollinarium [or one] will bend to the center, as they [pollinarium] will actually swivel where the caudicle attaches to the viscidium, so that when the butterfly sticks its proboscis down into the nectary tube, the pollinia will directly hit the central stigmatic surface.
In this series of pictures we see a Spicebush Swallowtail [Papilio troilus] Butterfly in the act of pollinating Platanthera ciliars. You can see, attached to the eye pollinarium, which it has unknowingly removed from the flower. The pollinarium, the male part of the flower, contains the pollinia which will hopefully brush up against and come into contact with the stigma [the female part of the flower] of the next flower it visits.
This set of pictures shows Spicebush Swallowtails [Papilio troilus] pollinating Orange Fringed Orchids [Platanthera ciliaris]. You can see pollinarium [the male part of the flower] attached to the butterflies eyes in some of the pictures. When the butterflies leave the flower they pull the pollinarium [which is full of pollen] from the flower out of the anther sack, which is now stuck to it's eye. Then moving to a second flower brushes the pollen [on the tip of the pollinarium] onto the stigma [the female par] of the flower. In this way pollination has been achieved.
These pictures show the pollination of Orange Fringed Orchid [Platanthera ciliaris] by a Spicebush Swallowtail [Papilio troilus]. As the Butterfly sticks its proboscis deep into the flowers spur, its eye comes into contact with the anther sack, and the viscidium, which is sticky [picture 1]. When it leaves the flower it pulls the pollinarium [the male part] from the flower out of the anther sack, which is now stuck to it's eye [picture 2]. When the Butterfly enters a second flowers the end of the pollinarium, which is made up of tiny grains of pollen, brushes up against the stigma, the female part of the flower, and deposits the pollen [picture 3, grains of pollen on the stigma]. In this way pollination has been achieved, the truly amazing world of orchid pollination.
Figure 1
I have always wanted to try to better understand the pollination of orchids in more detail, and thanks to a spider my understanding of the mysteries of pollination have become a little clearer, at least for Platanthera species. I was watching a Hummingbird Clearwing Moth (Hemaris thysbe) moving from one P. blephariglottis to another when it suddenly stopped moving, and on closer inspection I found the moth had been caught by a well-camouflaged Goldenrod Crab Spider (Misumena vatia). The picture that I took enabled me to see the things that I normally wouldn’t have seen or noticed. Having travelled to many flowers, this moth was covered in pollinaria. With help from people more versed in the subject of orchid pollination then I will ever be, as well as doing my own research plus the picture that I took on that day, I now have a much better understanding of the wonderful and fascinating world of not just orchid pollination, but all flowers and their unique relationships and dependence on specific insects to achieve pollination and thus the continuation of its species.
[Figure 1]Shows the original picture, and [Figure 2] Is cropped to show how the flower of a White Fringed Orchid is pollinated. The moth is lured to the flower by a fragrant scent and the promise of a sweet reward. The flower in question has two anther sacs, which contain the pollen, these two anthers or anther sacs are separated by a gap in the middle and are parallel to one another. It is in this opening or gap between the two anthers that the moth places it's head the thus it’s proboscis into the spur. While probing deep within the spur for nectar, the moth’s eye is forced to come into contact with the viscidium, which is located at the tip of the anther, and it [the viscidia] are also sticky. As the moth leaves the flower, and as it does so, pulls the pollinarium out of one or both anther sacs.
[Figure 1]Shows the original picture, and [Figure 2] Is cropped to show how the flower of a White Fringed Orchid is pollinated. The moth is lured to the flower by a fragrant scent and the promise of a sweet reward. The flower in question has two anther sacs, which contain the pollen, these two anthers or anther sacs are separated by a gap in the middle and are parallel to one another. It is in this opening or gap between the two anthers that the moth places it's head the thus it’s proboscis into the spur. While probing deep within the spur for nectar, the moth’s eye is forced to come into contact with the viscidium, which is located at the tip of the anther, and it [the viscidia] are also sticky. As the moth leaves the flower, and as it does so, pulls the pollinarium out of one or both anther sacs.
Figure 2
Figure 3
In [Figure 3] we get a closer look at just what it is the moth has removed from the anther sac[s]. Again, that which is stuck to its eye is called the pollinarium, the male part of the flower. You can clearly see the viscidium at the foot of each pollinarium, like little pads stuck to the moth’s eye. The yellow tube is known as a caudicle, and it connects the viscidium to the top, which is the pollinium, and forming each pollinium are many massulae, which are made up of tiny grains of pollinia that are bound together by viscid threads. The hope is, for the plant anyway, that when the moth visits the next flower and puts its proboscis in the spur that the pollinia, now attached to its eye, will brush against the stigma [Figure 4], the female part of that flower, and thus pollination will be achieved. What an ingenious trap the orchid has sprung on the moth to ensure that it gets pollinated, by directing the head of the moth and its eyes to line up with anther sacs, and leaves with the pollinarium which has the pollinia and then on to a stigma. For me this is just another example of the marvel of nature’s designs and engineering that I have spent countless hours photographing and trying to understand and now all because of a spider have a much clearer idea of just what I am looking at and feel privileged to witness.
It truly remarkable to think about how flowering plants form such specific and often complex relationships with insects to achieve pollination. Yet it is important to remember that these relationships do not form quickly, and instead are the result of trial and error over long periods of time. So, what we see before us today is nature at its best and is truly a work of art and perfection at its finest.
I would also like to state that I have on many occasions witness Spicebush Swallowtail Butterflies [Papilio troilus] on Planthera blephariglotis and it too has the long proboscis necessary for reaching down inside the spur of this flower and thus coming into contact with pollinarium inside the anther sac.
Figure 4
And this is only the pollination of Platanthera species discussed here, I can only imagine the other wonders waiting for me to discover in other orchid species and their amazing pollination.
It truly remarkable to think about how flowering plants form such specific and often complex relationships with insects to achieve pollination. Yet it is important to remember that these relationships do not form quickly, and instead are the result of trial and error over long periods of time. So, what we see before us today is nature at its best and is truly a work of art and perfection at its finest.
I would also like to state that I have on many occasions witness Spicebush Swallowtail Butterflies [Papilio troilus] on Planthera blephariglotis and it too has the long proboscis necessary for reaching down inside the spur of this flower and thus coming into contact with pollinarium inside the anther sac.
Figure 4
And this is only the pollination of Platanthera species discussed here, I can only imagine the other wonders waiting for me to discover in other orchid species and their amazing pollination.
Figure 4
I would like to thank Doran Horning for all his wonderful help with the graphics and his help in making my ideas more than just ideas. And also thank those who took the time to explain just what it is that I have been trying to capture all these years through my photography, the intricate and beautiful word of orchid pollination.