Papilio machaon [European Swallowtail]

[nfoto]

Rørslett, Birna (2022) Papilio machaon Linnaeus, 1758 (Papilionidae) European Swallowtail. Butterfly photographed in visible and ultraviolet light. LINK

 

Location:  Norway

 

Synonyms:

(See reference below for lengthy synonym list.)

 

Other Common Names:

• Old World Swallowtail
• Yellow Swallowtail

 

Reference:

1. Wikipedia (acc 29 Oct 2023) Papilio machaon. Wikimedia Foundation, San Francisco, CA. LINK

 

Comment:

A close friend of mine has found himself debilitated by a chronic disease and turned to rearing butterflies instead of going camera-hunting for wildlife. I visited him recently and as he had been curious about any UV response of his butterflies, I brought with me a small UV setup.

 

This European Swallowtail, Papilio machaon, either the nominal race or one of the 40+(!) other subspecies, had just emerged from its pupa and decided to take a break in its flittering activities. I snapped a visible light picture with my Z fc, then managed a short stack with the Nikon D3200 (built-in Baader-U) and the UV-Nikkor.

 

The appearance of this specimen was on the pale side, but the signature red dot on its tail is easily visible. The image is also a proof I am not adept at snapping butterflies!!

 

 

For UV, the creature decided to stay put, thus I could polish the outcome a little better,

 

 

 

On the site of collection, this butterfly foraged on Cardamine pratense, thus I could not resist the temptation to digitally arrange its flight back to the origin, The flower meadow being shot in UV of course.

 

 

My friend and I agreed we should follow-up with more species later.

 

[Andy Perrin]

Less fancy colors in UV, but it's not surprising considering the colors (real or false) are made by iridescence, and are clearly optimized for visible wavelengths. As with diffraction gratings, the spacing of the repeating patterns in the wing texture is critical to the resulting colors. The same spacing is unlikely to work for two different bands of light, any more than our dichroic filters would.

[colinbm]

Are these a legless species ?

[nfoto]

No.

[Fandyus]

Great, we definitely need more insect UV photos in here.

Or food, there surprisingly haven't been many food pictures.

Or hey, you could combine those two, if you like insect cuisine..

[Nate]

Interesting UV colors, I would have expected something different. We definitely need more of these.

 

[ulf]

8 hours ago, Andy Perrin said:

Less fancy colors in UV, but it's not surprising considering the colors (real or false) are made by iridescence, and are clearly optimized for visible wavelengths. As with diffraction gratings, the spacing of the repeating patterns in the wing texture is critical to the resulting colors. The same spacing is unlikely to work for two different bands of light, any more than our dichroic filters would.

Are all butterfly wing-colours structural?

[Andy Perrin]

7 minutes ago, ulf said:

Are all butterfly wing-colours structural?

No, I think I saw that sometimes the undersides are pigmented. (I do think the majority are structural -- the structural colored objects all have that strong angular dependence that we also see in dichroic filters, and most of the butterflies I've seen also have that look.)

[ulf]

I thought, some were structural, but not all and did some browsing on the web.

There are many interesting papers on the subject and it looks like there are both structural and pigment driven colours also on the top of the wing.

https://www.google.com/search?q=butterfly+scale+color&tbm=isch&chips=q:butterfly+scale+color,online_chips:melanin:rpgrz5oFWJE%3D&hl=en&sa=X&ved=2ahUKEwjk3MKbzo32AhWxSEEAHYbDBXMQ4lYoAHoECAEQHA&biw=2045&bih=1169#imgrc=X1Ee52NkHVQ-hM&imgdii=pnZE_f47GkMH8M

 

The iridescent ones naturally are structural, but many or some are not only depending on the structure, but also melanin pigments.

 

Without more knowledge it is impossible to  say how much each are used. 

Many papers are investing and comparing just a few species and there are so many.

 

I think it would be a bit difficult to create a structure for a white area of a wing.

[Andy Perrin]

White would be quite easy - just use random transparent fibers and the scattering would make it look white. I don’t think every structural color is based only on diffraction. Scattering must be involved also. 

[Andrea B.]

Very cool to see this pretty butterfly in UV.

 

I think they are incredibly difficult to photograph in UV.

But with patience you can eventually catch a moment when they are still.