Dandelion bug, dandelion pollen

Charles Krebs · Post by **Charles Krebs** » Wed Apr 04, 2007 10:02 pm

Rik recently posted a nice pollen shot, and Tom said he'd like to see more pollen shots and added that:

Pollen is sort of challenging in the light microscope.

So I grabbed a few dandelions (I've got plenty!

), and when I started to collect some pollen, about 10 of these little bugs fell out of the flowers. I have often seen this small insect in dandelions, so I thought I would take a closer look at them as well as try for a pollen shot.

Tom is certainly correct. Pollen is tough with the light microscope. It is really a subject far better done with SEM. In this shot (taken with the 100X) I'm only satisfied with the one grain in the upper right.

Planapo · Post by **Planapo** » Thu Apr 05, 2007 1:34 am

Charles, amazing pictures as always! Thanks for sharing.

I´m especially fond of the "bug" shots. They are so rich in detail!
Even on the photo of the whole animal one can already recognize the extendable and retractable end part (arolium) of this insect´s foot. In German such a bug is sometimes called "Blasenfuß" because of this trait which translates to "bubble-foot".

The "bug" is a thrips, i. e. belonging to the insect order Thysanoptera.

(The word "bug" in the English language is confusing the heck out of a non mother tongue speaker. It seems all insects can be called "bugs", but there are the "true bugs", some call bacteria "bugs" aswell, then there are the "sow bugs" and "bugs" in software...

... bugs everywhere.. Argh!

)

Cheers,
Betty

Ken Ramos · Post by **Ken Ramos** » Thu Apr 05, 2007 2:53 am

I don't know Charlie but your images are outstanding as usual and pollen grains really are not all that photogenic for the light microscope it seems but hey you did a great job as usual bringing us these images. I have often noticed those little bugs too in Dandelions but never investigated them.

Something must be "bugging" Betty

Charles Krebs · Post by **Charles Krebs** » Thu Apr 05, 2007 8:07 am

Betty... ah yes... over here the word "bug" has (d)evolved to mean just about anything alive that is small, and, as you pointed out, the software variety as well!

In a forum like this I should not be so casual with language. Bug is really only appropriate for members of the order Hemiptera. To accommodate the inaccurate popular generic meaning, many, as you point out, will use the term "true bug" when talking about Hemipterans. While I knew this was an insect and not really a "bug" I still didn't know what it was, so thanks for the ID! BTW... your English is superb!

Ken... always fun to finally look closely at something you've "known" for years. So much to wonder about. For example, when I made the second image I could not help but wonder what purpose those two "thorns" on the antenna served. And the wings were very graphic and unusual looking. I even did an "abstract" b+w of a wing section.

beetleman · Post by **beetleman** » Thu Apr 05, 2007 12:50 pm

I always love opening up your posts Charles. There is always something new and excitingly beautiful waiting in the pictures you post. The thrips are truly amazing and for some reason I started to sneeze because of the pollen picture

Thomas Ashcraft · Post by **Thomas Ashcraft** » Thu Apr 05, 2007 1:50 pm

Charlie wrote : "Tom is certainly correct. Pollen is tough with the light microscope. It is really a subject far better done with SEM. In this shot (taken with the 100X) I'm only satisfied with the one grain in the upper right. "

Hi Charlie,

Thanks for posting the pollen pics. A SEM surely gets the intricate stucture of the grain........but doesn't capture the beautiful and distinctive pollen colors. (Actually, I'm not sure about that. Maybe there have been advancements made in electron microscopy regarding color that I am not aware of.)

Also, when I look at pollen under the microscope it seems to me to be quite "vital", radiant and alive, since it has sperm inside ready to do its thing. But SEM images of pollen look sort of ghostly to me.

I guess the full knowledge comes from a composite of views.

Tom

rjlittlefield · Post by **rjlittlefield** » Sat Apr 07, 2007 9:13 am

Thomas Ashcraft wrote:A SEM surely gets the intricate stucture of the grain........but doesn't capture the beautiful and distinctive pollen colors. (Actually, I'm not sure about that. Maybe there have been advancements made in electron microscopy regarding color that I am not aware of.)

Nope, no advancements like that, sorry. SEM's can produce pseudo-color images from energy spectra of the electrons, but there's no way for the SEM to tell how the subject would interact with honest-to-goodness 400-700 nm photons.

Another wrinkle with SEM's is that they only tell you about the surface. That's great for telling you about the shape of pollen, or of a freeze-dried protozoan. But if you want to know about innards, you need a different device.

--Rik

rjlittlefield · Post by **rjlittlefield** » Sat Apr 07, 2007 9:20 am

Charlie, these are beautiful pictures, as always.

I'm assuming stacked, but I have no idea how deeply.

And I'm really curious how you illuminated that high-mag pollen shot.

More details, please?

Thanks!
--Rik

Charles Krebs · Post by **Charles Krebs** » Sat Apr 07, 2007 8:42 pm

Rik,
The first image is from a stack of 7.

The second is a stack of 25. I got all of the antenna in about 8 images, but had to go another 17 just to "pick up" the antenna base and eye facets.

There are about 11 or 12 in the pollen grain image. This was illuminated using (transmitted) DIC. The grains are somewhat translucent, so some light comes through, and the DIC gives some direction and "shadow" to the light. Looking over the source files I could probably have done a little better job overall, but it would require a lot more time editing, and it really wasn't a fun one to work on.

rjlittlefield · Post by **rjlittlefield** » Sat Apr 07, 2007 10:31 pm

Charles Krebs wrote:There are about 11 or 12 in the pollen grain image. This was illuminated using (transmitted) DIC. The grains are somewhat translucent, so some light comes through, and the DIC gives some direction and "shadow" to the light. Looking over the source files I could probably have done a little better job overall, but it would require a lot more time editing, and it really wasn't a fun one to work on.

Charlie,

Thanks for the additional info. You might not guess from the spelling, but I'm starting to think of "pollen" as a "four-letter word".

I played with some birch pollen tonight, and got nothing but frustrated. Even analyzing by eye, I could not figure out for sure what the shapes were. The photos were abysmal. No interesting details like the projections that your dandelions have -- just smooth curves and big ridges that I'm still scratching my head over, wondering what's real and what's artifact.

You did a great job on these dandelion!

--Rik

PS. Google image search on "birch pollen" turns up this SEM shot, which (minus the fine texture) matches pretty well what I was seeing through the light microscope.

Cyclops · Post by **Cyclops** » Wed May 19, 2010 9:08 am

Wow these are great!!
We call these flies Thunder Flies over here and in summer one can get covered in them, especially when out cycling!

I love the pollen too, brilliant!