Pollinia attached to African insects.
The aim of this project is to find out which insects are visitors to plants that have pollinia. Please give some ideas how this project could be improved and made more useful. Perhaps those providing observations for the project could also include some information about which pollinia plants are flowering in the locality. These may be sources of the pollinia on the insects. Thanks for your interest in this project !
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There are two major groups of "pollinaria"-bearing plants.
Orchidaceae: these comprise a bit of glue containing a single anther cell with a shared stalk: there are only two pollinaria per flower. When visiting the flower a pollinarium is glued onto the visitor and as it dries out the stalk re-orientates the pollinarium to hit the stigma of subsequent flowers. The pollen is smeared onto the stigma. This is thus a "wet" pollinarium.
Asclepiadaceae. these comprise a clip holding a complete anther (two cells). When visiting the flower the foot or tongue of the pollinator is guided into grooves allowing the pollinarium to be clipped on. There are five pollinaria per flower. On subsequent visits the pollarium is guided to the stigma and removed in entirety by the same groove mechanism. This is thus a "dry" pollinarium.
As a rough rule, it is easy to ID pollinaria to family, but far more difficult to genera, and usually not to species. The easiest way to get an identification to species level is to follow the pollinator to a flower.
My question: If moths end up having to carry around these weighty pollinia, which must make flying use a little bit more energy, would we expect moths ( and other insects ) to evolve non-stick feet, without the hooks that pick up those annoying pollinaria, Have any insects managed to evolve better designed feet to avoid getting hooked up with a these.
botswanabugs https://www.inaturalist.org/observations/15348551#comment-2008108
This is an arms race. Yes, pollinators dont want the load, but flowers want the transport. Any adaptation by the insect will be matched by the flower.
In an ideal world the pollinaria will be removed on the next visit so the insect will only carry one pollnarium at a time. However, not all pollinaria are removed, especially in orchids where insects may visit many flowers before the stalk re-orientates. Some few insects may thus carry considerable loads. Birds are strong enough to remove glued pollinaria, and even clips from their tongues, but they generally visit a patch before grooming. I dont know about grooming in insects though: will they be strong enough or agile enough to remove the pollinaria - if it takes too long, it may be just as well to ignore them.
Thanks for this enlightenment @tonyrebelo . Just wonder what words we should use in the project. Pollinaria or pollinia, pollnarium.pollinarium, pollinium. Ill change the words if i have messed up ! Are pollinaria a food source for any insects, birds etc ? It will be interesting to see if the distribution of any moth species ( found with pollinaria) will be similar to the distribution of any Asclepiadaceae. particularly the more common ones like pergularia daemia or gomphocarpus sp which flower profusely in drier places.
Is there a differenece between pollinia and pollinaria ? I saw the two words used in the same title here. https://www.jstor.org/stable/41760316?seq=1#page_scan_tab_contents
There seems to be some ambiguity. Pollinaria are usually the entire unit, whereas pollinia are the anther sac portion of the unit. But other usages exist.
~ium is the individual, ~ia is plural. - One pollinarium, two pollinaria; one pollinium, two pollinia.
I found an interesting paper by our very own @craigpeter about the non-effects of high pollinium-loads on honeybees - https://www.researchgate.net/publication/228081861_Large_pollen_loads_of_a_South_African_asclepiad_do_not_interfere_with_the_foraging_behaviour_or_efficiency_of_pollinating_honey_bees
I seem to remember (from when I was at university back in the mists of time) - that the groove in the asclepiad flower is between stamens and the clip connects pollinia from neighbouring anthers (not 2 pollinia from the same anther). We need Ashley Nicholous for help here, but I don't think he migrated?
Yes that is correct: the arms connect adjacent anther sacs (of different anthers) in the Apocynaceae.
Thanks @peterwebb for the banner photo. I need to find a way of moving the protect title ! The great observation is here .
https://www.inaturalist.org/observations/10796618
Definition of pollinium/pollinarium according to Auntie Elizabeth Tootill:
pollinium The structure formed when individual pollen grains remain massed together and are transported as a unit during pollination. They may be held together only by sticky secretions or they may be retained within the pollen sac wall, as in many orchids. When several pollen sacs remain together and are transported as a pollination unit they are called a pollinarium.
Source:Tootill, E. 1984. The Penguin dictionary of botany. Penguin Books, Harmondsworth, England.
This would make orchid and asclep pollen masses pollinaria. Unless I am very much mistaken...
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