French Blue

[NickMorgan]

Can anyone help a colleague identify a butterfly he saw in the Loire Valley a couple of weeks ago. He suggests that it may be a Common Blue. I wasn't so sure, until I saw David M's personal diary with a picture of a female Common Blue he had seen.
Over to the experts ...

[David M]

I'd be very surprised if this were a female Common Blue. The ground colour is far too pale and the forewing spot is quite pronounced.

That said, I'm struggling for alternatives, so I hope one of our European specialists can drop by and put us both out of our misery. Could it perhaps be a female Adonis Blue (though even that would be bizarre given the extent of blue suffusion)?

[Padfield]

Wow!

Wow!

Certainties first: this is Lysandra (or Polyommatus, subgenus Lysandra).

The flight time points very strongly to bellargus, given that this doesn't remotely resemble hispana. But as it doesn't resemble bellargus either, this can't count as a certainty! The colour is most unusual.

I'm not even sure about the sex. I incline towards male but am wondering if it might be gynandrous (not bilaterally - mixed, in some strange, symmetrical way).

Fantastic butterfly - I'm going to do some research!

Guy

EDIT - I think I take back the male bit. After comparing this butterfly with some pictures of ceronus it seems to be an extreme version of this aberration - hence a female. The abdomen was a bit ambiguous to me - short but rather narrow - so a fresh, virgin female.

[David M]

Trust you to pick up on something others failed to detect!

You're right. The abdomen doesn't exactly 'scream' female at the observer. However, which male spring flying species of Blue looks like this?

Could it perhaps be bellargus form ceronus? According to my European guide, this is locally common in "west and south west France".

If not, then could we be looking at a hybrid?

[Padfield]

David - I edited my comment while you were typing yours! I agree - this is super-ceronus! Maybe that has a name - or maybe everything I've hitherto called ceronus simply wasn't the real McCoy ...

Guy

Here's a rather similar butterfly:

http://www.visoflora.com/photos-nature/ ... lyomm.html

[David M]

Thanks for that, Guy.

Like you, I think this butterfly is particularly stunning. It's amazing what nature can throw up and I'm already looking forward to the day when I can visit that part of France and see one myself.

[NickMorgan]

Thank you Guy and David.
I'm feeling a little proud of myself as when my colleague showed me the picture this morning I thought that I had never seen anything like it, but that Adonis Blue sprang to mind because of the black markings on the white fringes. But that was as far as my VERY limited knowledge of European blues went! I am very glad that it is something unusual, though. That makes me feel a little better for not knowing!!
It is a lovely butterfly, whatever it is! Some female blues are really spectacular. Some day I will have to visit southern Europe at the right time of year to see a good variety of blues.