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In the hills behind my house in Spain i either get Spanish Swallowtail Iphiclides feisthamelii, or Swallowtail Papilio machaon (photo 1). Last year I took a few shots of this dark form of (I'm assuming) machaon (photo 2) and was wondering if anyone knew how common/rare it was.

1


2


Thanks for any help in advance,

Martin.

I can't recall ever having seen a swallowtail like this! Variation is supposed to be relatively infrequent in machaon but several rare melanic forms have been named and this certainly seems to be a case of mild melanism. Was it one of a kind or is it recurrent in the area?

Guy

Nice photo's Martin, and a very lucky find.

At first I thought ab. hiemalis but there is a key feature on your specimen which is the yellow 'eyes' on the hind wings, rather than the usual orange/red. This is an additional aberration that one wouldn't expect with 'pure' hiemalis.

It's plausible that this specimen is exhibiting characteristics of two distinct genetic aberrations.

Guy probably knows a lot more than more here though, so over to you...

Felix.

Hmm. yes yes.

I've done a little research and the characteristic of ab hiemalis is the occlusion of the blue markings on the hind wind inner margin with black scales, together with heavier black scaling in the more usual areas.

Those yellow eye spots are something else though. So I suppose that one could say that yours is ab hiemalis + ab ?????

Felix.

Ps. hiemalis means of or pertaining to Winter. Odd name, I can't see it myself...

Over to you, Felix!! I'm learning! I looked up your hiernalis on the Cockayne site and it certainly seems to match this butterfly, apart from the yellow spot.

In apollos the usual red spot on the hindwing fades to pale orange/yellow as the butterfly ages. Is it possible we are seeing the same transition here? It is the same family

Guy

Guy,

Of course! and Martin's specimen is clearly old (or at least well weathered!) that would explain it.

Mystery solved.

Incidentally (and on a totally unrelated note), if you're interested in interspecific hybridization in European butterflies take a look at this paper - it's very interesting indeed. The only reason that I mention it is because I recently read it and it explained an awful lot about the taxonomic headaches with the European butterfly fauna.

http://www.ucl.ac.uk/taxome/jim/pap/des ... llet07.pdf

Anyway, better get back to work

Felix.

Thanks for the link Felix - that paper is very educational! I particularly like the summary of characteristics in the appendix that are used to distinguish species.

My son liked the felt-tipped-pen colouring and claims he could have done better

Cheers,

- Pete

No problem Pete.

Is it my imagination or did you at some point in time request information on an work (a key) that aids in the identification of the aberrations and subspecific forms of British Butterflies?

If you did I have the answer.

If you didn't, please ignore this post!

F.

This is something I’ve wondered about. Having seen quite a few papilionidae (festoons) at the end of their flight periods, they seem to lose their red and blue scales more easily than other scales. Here’s a photo of an aged Southern Festoon (zerynthia polyxena) that gives no indication that it ever had magnificent red and blue scales.

Felix wrote:No problem Pete.

Is it my imagination or did you at some point in time request information on an work (a key) that aids in the identification of the aberrations and subspecific forms of British Butterflies?

If you did I have the answer.

If you didn't, please ignore this post!

F.

Hi Felix - I might well have done! Currently, I use Adrian Riley's book as the main source of identifying subspecies, and the Cockayne database for aberrations (and the books I have).

What do you have in mind?

Cheers,

- Pete

I thought you did. Good, at least that means that one of my mental faculties is still functioning fairly well.

A vast manuscript entitled Aberrational and Subspecific Forms of British Lepidoptera, Part 1 - The Rhopalocera by Goodson & Read was put together a few years ago by the BMNH for their internal use.

In 4 volumes (for the rhopalocera alone!) It's a vast tome and it will, through the key, tell you the specific differences between all the different named abs (ranging from 7 for the white letter hairstreak to around 500 for the chalkhill blue) as well as all the subspecific forms.

Since it is the policy of the BMNH to no longer name any new aberrations (?why) it is an exhaustive guide.

If you're analytical and like to put a name to something it is invaluable. If you're an aesthetic and simply like to admire the intense beauty of the living creature it will be a bore.

Felix.

Any idea how to get hold of a copy?

Cheers,

- Pete

Thanks Felix! I shall print off that pdf on the school printer and read it tonight with my Shrove Tuesday whisky (long dry spell forecast!!). I have observed the trend towards lumping at generic level and splitting at specific level with interest (cynically, I had assumed the latter was so zoologists could get their name to something now we don't name aberrations!!).

Fascinating picture of the festoon, Roger! The crescents on the hindwing that should enclose red do seem to enclose a rather dull yellow.

Guy

Felix wrote:Ps. hiemalis means of or pertaining to Winter. Odd name, I can't see it myself...

Well, melanism and cold do go together. Alpine forms are frequently much darker than their lowland cousins. Many non-genetic colour variants have also been produced by temperature experiments in the laboratory. Perhaps hiernalis is governed by some low temperature trigger?

Guy

Well, melanism and cold do go together. Alpine forms are frequently much darker than their lowland cousins. Many non-genetic colour variants have also been produced by temperature experiments in the laboratory. Perhaps hiernalis is governed by some low temperature trigger?

Of course! It would make sense too - darker colours would be more efficient at absorbing solar energy.

Felix.

About three years ago, I got the following email which seems to relate to this topic. The first of the two links is not very interesting, even if I could read Swedish, but the second (psigate) link may be of interest. I don’t think the topic is restricted to M. daphnis, as it seems to apply to all Lycaenidae species. Guy, I think I copied you at the time and you responded to Professor Bjork.

Dear Mr. Gibbons,

I am a professor of physics teaching an introductory course on
Electromagnetic field theory and waves. Each year, on the course home-page
(last year's home page can be found at
http://www.imit.kth.se/courses/2B1350/kursomg04/), I put a small
illustration of interfering waves, to spur the students' interest in the
subject, to provide a visual element to an otherwise rather boring
www-page, and to show that waves play a role in many interesting and
visually pleasing phenomena we observe.

This year I would like to put one of your photos of a Meleager's Blue
(Meleageria daphnis) on the page. The intense blue color of the butterfly
is caused by diffraction of white light in the regular microstructure that
covers the butterfly's wings. I have never (knowingly) seen a Meleager's
Blue myself, but I expect that the color should change depending on the
viewing angle of the wing. If you are interested to learn more about the
phenomena, then please see, e.g.,
http://www.psigate.ac.uk/spotlight/issu ... erfly.html

The permission I am asking for is for a one-time, non-commercial use of
the photo. I will of course display: "Copyright Roger Gibbons, reproduced
with permission" under the photo.

Sincerely Yours

Gunnar Björk, Professor, Royal Institute of Technology, Stockholm, Sweden

Check out these two pictures of large blue, the first from the Alps and the second from the Pyrenees. They must presumably have developed these melanic altitude forms independently:




I was really excited about the second until I got close enough to examine it carefully because I thought it was teleius, which had allegedly been reported from the Val but never confirmed. I wonder if it was this form that gave rise to those reports.

Guy

PS - yes, I do remember that correspondence, Roger!

Guy

Any idea how to get hold of a copy?

Cheers,

- Pete

I have sent you a PM Pete.

Felix.

Hi Piers ... er ... Felix

For some reason, private messaging isn't working (I've contacted my ISP to get this sorted). If you could email me at pete@ukbutterflies.co.uk I'd appreciate it.

Cheers,

- Pete