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Attached image was taken in the French Alps in 2017. A positive ID would be great if possible but appreciate it is a worn specimen (I'm leaning towards serratulae but probably way off the mark!).

Can you give us an altitude - and a date?

Guy

Hi Guy,

The image was taken on July 6th 2017 during a trip to the Col de la Cayolle although below the summit - i would guess the altitude to be in the region of 1500 metres. Hope this helps and apologies for not being able to pin down the altitude.

Kevin

Wasn't this the trip you came on with me?

I can only think this location was at Lac d'Estenc, or very possibly some hillside meadows a couple of km further up the road towards the col.

It's a tricky one, and without an underside I couldn't be certain, but I've eliminated the ones I'm confident it can't be and am left with either serratulae or alveus.

Hi David,

Yes it was on the trip with yourself. I think the wayside meadows further up the road is most likely. Appreciate it is a difficult one to accurately ID. Having said that it suits my purposes exactly as I’m giving a presentation on butterflies to my local camera club (Cwmbran) and identification is an obvious topic - Pyrgus are a classic example!

Kevin

There is considerable geographic variation in these species, so my experiences from Switzerland may not make me a reliable judge for that part of France. Nevertheless, for what it's worth, I would put carlinae very firmly in the picture. The books always stress the 'C' mark but this is not constant and the shape of the cell mark in this individual is well within the range of variation. Male carlinae typically has rather strong markings on the forewings and often weak markings on the hindwings. In Switzerland, alveus is typically rather dotty on the forewing, with well separated markings, and I wouldn't consider this butterfly for that. Serratulae is so variable above I generally like to see an underside before confirming! This butterfly is within the range of variation for serratulae.

So that's the Swiss vote. Either carlinae or serratulae, probably with a preference for carlinae but without much confidence.

Guy

My twopennyworth - I agree the carlinae cell spot is within the range of variation, but at the edges, so maybe less likely on a probability basis.

We have seen earlier this year that serratulae can have stronger upf markings but it would appear that this was in the first generation. This was in July, when it seems our broad experience is of more lightly marked serratulae upf, so I suggest it would be unlikely to be as heavily marked as this.

I would add Safflower Skipper (P. carthami) to the mix. The squarish markings are redolent of carthami in my experience, an example below. I have quite a few records of carthami from Estenc up to Cayolle, so my experience is that it is fairly widespread in the region.

With only an upperside view, compounded by that amount of ageing, it is, I suggest, a matter of best guesses.

Roger

Thanks for your input gentlemen. It is, as I thought, not possible to provide an accurate ID.

My two cents: just based on the upw my best guess would be serratulae. Especially the uph looks quite typical for serratulae from this region with the combination of a carthami-like string of submarginal spots (although being less whitish, less long, less narrow and less clearly demarcated than the latter - and these differences often being exaggerated in worn individuals) and a non-splitted and apparently lonely discal marking. The quite obvious uph markings wouldn't really bother me with regard to serratulae of this location (https://vlinderszuidfransealpen.blogspo ... th-my.html).

That being said, as often with these pyrgus, a look at the underside might flip tentative thoughts instantly.

Kind regards, Bert-Jan Luijendijk

I usually begin trawling through my previous summers Skipper images in the Autumn and assign them pretty quickly to serratulae. I then spend the winter trying to reassign them to a species I would rather they were . By spring they are returned to the serratulae file . I am not aware of any population level information in Europe but , it seems to me that serratulae is the skipper that is easiest to find and photograph in European mountains