UVR Batesian Mimicry of Social Wasp (Vespula sp.) by Hoverfly (Episyrphus balteatus)

[Andrew Dayer]

Some hoverflies such as the marmalade hoverfly(Episyrphus balteatus) have been cited in the literature as examples of mimics of social wasps such as Vespula sp gaining protection from birds due to their visual similarity (yellow and dark strips).

 

I happened to be doing some UVR stuff yesterday on a conventient Hypericum with some of the marmalade hoverflies photo-bombing my images. Well, they were there first, I suppose...

 

The hoverflys do have patterns in my UVR images and some of the literature claims - but doesn't give evidence - that wasps also do. As the test protocol in the literature involved showing pigeons (who presumably do seen UV) printed images of insects (presumably printed in RGB for human eyes), I felt uncomfortable about the protocol.

 

I did a quick look at the only wasp specimens to hand - a hornet and a common wasp, both dead - with the UV torch and liveview. Both looked very dark and unpatterned to me but I don't know if this is just post-portem. Unfortunately, I can't find live specimens right now - its a pretty grim year for insects in the UK.

I've searched here under 'wasp' and 'vespa' with little luck - does anyone have any UVR images of live wasps or have noticed them in passing?

 

For interest, one of the Hyperium images with male (left; flying) and female (right) marmalade hoverflies (Episyrphus balteatus).
Nikon D3200 FS; UV-Nikon 105mm; Baader-U; single hand-held Vivitar 285HV FS (1/1 power) & sunlight. 1/200 @ f16; ISO 800. Processed in Lightroom (custom WB; tweaking).

 

[colinbm]

Beaut photo.

[Andrea B.]

Wonderful capture of the hoverflies - and of the Hypericum too.

 

We need more insect photos here on UVP, but they are often difficult to make.

 

 

[Andrew Dayer]

@colinbm and @Andrea B. - thank you both. High praise indeed.

I suspect most insects and other animals - I've looked in UV at historical collections or beeltes, butterflies and moths, and birds - are pretty dull which I find surprising given their eyesight. Still, I like the "other worldly / alien" perspective of UVR even with false colour.

The image above was just a screen grab; here's a better version and another image from the same session.

I might try again with a second flash and diffusion.

 

 

 

[colinbm]

Thanks for the extras.

 

[ulf]

8 hours ago, Andrea B. said:

Wonderful capture of the hoverflies - and of the Hypericum too.

 

We need more insect photos here on UVP, but they are often difficult to make.

 

 

I had a topic here with insect photos :https://www.ultravioletphotography.com/content/index.php?/topic/3780-crowded-bug-vision-flies/&do=findComment&comment=34177

Unfortunately I am not allowed to open that topic now and get this error message:

[Andrew Dayer]

8 minutes ago, ulf said:

I had a topic here with insect photos :https://www.ultravioletphotography.com/content/index.php?/topic/3780-crowded-bug-vision-flies/&do=findComment&comment=34177

Unfortunately I am not allowed to open that topic now and get this erroro message:

 

 

Me too...

[ulf]

I can download and re-upload the pictures, but unfortunately I do not remember what I originally wrote.

 

The filter used is a BUG stack of  S8612, 2mm and possibly a UG5, 1.5mm

The camera was my FS-self converted Canon 60D.

 

The second image with the marmelade hoverfly show the size of the flower and that the flies are tiny. They were metallic green with green eyes in VIS too, but the wings were a bit more transparent if I remember correctly.

 

I think I have more images in IR too with these flies.

I'll search and add the if I find them.

 

[nfoto]

Even with admin privileges I'm denied access to that topic. Strange. *Very* strange.

[dabateman]

6 hours ago, ulf said:

I had a topic here with insect photos :https://www.ultravioletphotography.com/content/index.php?/topic/3780-crowded-bug-vision-flies/&do=findComment&comment=34177

Unfortunately I am not allowed to open that topic now and get this error message:

You must have captured some top secret government spy bug. 

Locked so no one can see it now.

 

Sweden is very protective of their spy bugs.  

 

[ulf]

I I found a VIS image and a NIR image of the flies:

The NIR image is blurred to avoid disturbing moral sensitive viewers.

 

 

 

[Andy Perrin]

I love this topic, including the original photos by Andrew. So many great pictures.

[Andrew Dayer]

Lovely images, @ulf. Any idea what lens you used; one of the enlarger lenses maybe? My success rate - sharp with enough DoF - with close-up and macro is just not good enough yet. Doubly so in UVR with only the D3200's fuzzy, low contrast pink live view. Practise needed, I expect .

[ulf]

Thanks Andrew.
I am confident that it was my EL-Nikkor 80mm old metal lens.

After five years all settings are forgotten, but I guess it was f/11. I can see the exposure time from the exif data in the raw files.

 

That day, 2017-07-14, and location was perfect with good illumination and almost no wind. 

I made some mistakes focussing with the IR image and also with a BG3, 2mm - S8612, a 2mm stack and a Baader U filter.

 

[ulf]

Here is the UV-version taken with a Baader U filter.

The face and eyes of the fly is not in focus. A bad portrait!

[Yves W]

Very beautiful and very interesting

A lot of patience, at home a lot of wind by the sea

Thanks Andrew and Ulf

[Andrew Dayer]

I can now answer my own question having found a live wasp in the house.

 

In similar conditions to the hoverfly images, except for the lack of sunlight, the live wasp I found as overall very dark like the dead specimens.

 

Due to lack of competance, the images I created were pretty rubbish - poor exposure and focus - this one is severely hacked but makes the point adquately, I think. Likely to be Vespula vulgaris, the common wasp but can't exclude it being Vespula germanica. Posed on an apple...

I think the assmption in the original paper (Bain, R.S., Rashed, A., Cowper, V.J., Gilbert, S.F., Sherratt, S.N. (2007). The key mimetic features of hoverflies through avian eyes. Proc. R. Soc. B (2007) 274, 1949–1954 doi:10.1098/rspb.2007.0458) about UV not been relvant is not supported. Seems to me that hoverflies look more like wasps than wasps do in UV.

Post-script. Not sure why I used 'vespa' in the thread title or first post. Should have been 'Vespula sp'.

 

[Andrea B.]

Andrew, I'll change Vespa -> Vespula for you.

[Andrea B.]

Ulf, the link to your topic has been restored.

 

https://www.ultravioletphotography.com/content/index.php?/topic/3780-crowded-bug-vision-flies/

[Andrew Dayer]

On 7/25/2023 at 4:55 AM, Andrea B. said:

Andrew, I'll change Vespa -> Vespula for you.

Thank you!

[Andrew Dayer]

Dumb Question - What Am I Seeing Here?

 

I thought about a new thread for this but maybe it fits OK here.

When made the first images in the sequence above, I had forgotten to remove the Nantong Foric ZWB1 2mm x2 filters that I had on the Vivitar 285HV FS flash. The resulting images looked odd and I forgot about them until the other day. Other settings were as above Nikon D3200 FS; UV-Nikon 105mm; Baader-U; single hand-held Vivitar 285HV FS (1/1 power) & sunlight. 1/200 @ f16; ISO 800. Processed in Lightroom (no WB, extended (temp & tint -100) via DNG method) only; no other adjustments).

 

Dumb question: given the ZWB1 / Baader U / D3200 FS sensor combination, is it reasonable to think this image was made with a peak wavelength somewhere around 350nm? If so, the hoverflies patterning at this wavelength is of note. I'm painfully aware I did nothing to provide calibration on the day; for info PTFE sheet imaged in similar conditions also shows yellow tone.

[Andrea B.]

The ZWB1 passes UV, a tiny amount of violet,blue (a toe's worth maybe) and also a chunk IR light and it is on the flash.The BaaderU passes UV peaking around 350 nm. The BaaderU should block almost all of the visible and IR light. There might be a little bit of flash IR getting through the BaaderU.

But, yes, I think this is probably a photo around 350 nm.

 

The white balance is atypical. If you upload the raw file, I'll run it through raw digger.

[Andrew Dayer]

@Andrea B. Thanks for your feedback, Andrea.

My post was a little misleading - now edited to correct I hope - in that I had not performed a white balance in Lightrrom but used a profile with an extended temp & tint range of -100 via the Abode DNG profile editor. This processes - demosaics I suppose - the image away from the 'normal' pink hues with seen profiles intended for regular visible light images. It give acceptable results compared with other folks' work and does allow the profile to be applied to a batch when importing to Lightroom. But I would be really interested to see what you find via Rawdigger, thank you for the offer (its on my to-do to look at that tool). RAW attached here (is that OK to do here?).

This is what the image looks like with the custom profile, after stretching the tone to the limits of dynamic range ie just before clipping of whites and blacks, and after arbitary WB. Please do feel free to point out flaws in this method. A rather unsharp and noisy image.

DSC_1097.NEF

[Andrea B.]

Just an observation from my own experience. It is sooooo difficult to make a UV photo of a flying insect!!

Your fly is mostly in focus and its UV-signature is clearly shown. Good! 

 

I am always cautious about making any judgements based on false color though. Be very careful there.

 

The raw composite shows, for the flowers, the typical raw color of a BaaderU photo.

 

 

Here is a rendition from Photo Ninja. It was difficult finding just the right spot on which to make the white-click. Typically there should not be an overall yellow cast to this photo **if** you are trying to standardize the WB for comparison purposes.

Also, the blue shadows on the petals are unusual so I suspected something else is going on. See next.

'

 

 

There is some kind of flare or light leak. There are usually not violet/blue-ish shadows and an entire blue background. And of course the big blue streaks are on the left anomalous.

To show this problem I raised the illumination (brightness) in Photo Ninja to bring out the background.

 

 

 

 

Here's an old Hypericum photo I made in 2007 with a D200 and a BaaderU on the UV-Nikkor. This is the raw composite (no white balance) to show you another example of the orange petal colors recorded with a BaaderU peaking around 350 nm. If filtration was moved "to the right" with pieks in the 370 -380 nm range, we'd begin to see the raw colors move towards a pinkish-magenta and eventually a reddish-violet. 

 

 

 

Hope this helps!

[Andrea B.]

Crop of the little hover fly. (Slightly diff false color because made from another try at white balancing.)