Skippers form Vanoise, French Alps

[Steve Babbs]

Hi all

I know they're a nightmare to identify but, just in case, can anyone help with these skippers from Vanoise, this August? Photos 2 and 3 are the same species. Large Grizzled Skipper? The other Oberthur's Grizzled Skipper? Mainly going on advice from someone else.

Regards

Steve

[Roger Gibbons]

The underside looks good for Carline (Pyrgus carlinae), although if #3 upperside is the same butterfly, I might be less confident, albeit too worn (the skipper, not me) to enable any conclusion.

The #1 upperside is very hard to say without an underside shot (we always say this, but very often it is just impossible to get both surfaces), but I feel Carline or Large Grizzled (P. alveus) are the two strongest favourites. The books usually refer to the C-shaped upf cell spot of Carline, and it is true that a clear C-shape is very strongly indicative of Carline, but the range of this mark for Carline extends to “just slightly” C-shaped. It is unusual for other Pyrgus to have even “just slightly” C-shaped marks in my experience. So, if pressed, I would go for Carline for the upperside.

Roger

[Steve Babbs]

Thanks Roger. I tried, but completely failed, to get an underside shot of 1. It's definitely a different individual to the next two which are shots of the same individual.

[Padfield]

My guess for the first one was carlinae. I'm sure Roger is right to hedge his bets a little on it, as Pyrgus uppersides can be extremely variable, but it's difficult to see alveus there.

The second = third one is much more of a puzzler. As Roger says, the underside looks good for carlinae and would be quite anomalous for either armoricanus or alveus. But the upperside really doesn't look like carlinae. The problem is, it doesn't look like anything that could have that underside. In fact, I don't believe it is the same butterfly. Comparing what is visible of the right forewing apex of skipper 2 with that of skipper 3 I think they are clearly different individuals ... In my opinion, the second picture shows carlinae, like the first, and the third shows a different species - possibly a worn alveus or armoricanus.

Guy

[David M]

Comparing what is visible of the right forewing apex of skipper 2 with that of skipper 3 I think they are clearly different individuals ...

Skipper 2 looks much fresher than skipper 3, and (though this might be a trick of the light), specimen 3 has a white arc behind its left eye, whereas in specimen 2 this is much darker.

[Roger Gibbons]

I agree, I don't think #2 and #3 can be the same butterfly. Apart from the colour issue, the three marks in s7 adjacent to the costa (just visible in the underside shot) do not match the upperside shot.

I agree with Guy, adding the rider that alveus is more likely than armoricanus as the latter is generally not a high altitude species and has an upper altitude limit of around 1700m and Steve may have been higher than that in the Vanoise.

Roger

[Steve Babbs]

It does seem I've jumped to conclusions about two and three being the same individual because they were taken a few seconds apart. Here is another photo of the one showing its underside with a bit upperside.

[Padfield]

Well, that's conclusive! It's carlinae. So I think you can safely call 1 and 2 this. For me, the jury's out on 3, pending data on altitude &c., as Roger says. The more I look at it, though, the more alveus seems probable. This is a very variable species throughout its range.

Guy

[Steve Babbs]

Not for the first time, many thanks to Guy and Roger for your help. It's very much appreciated.