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A trip abroad wouldn't be complete without a pyrgus mystery.

Both myself and one of the group took images at different sites of an unusual looking pyrgus.

Here's mine (1,200m, dry, arid site):
...and the other image from a different location:
They didn't have the reddish undersides that cirsii possesses, but I'm struggling to see an alternative, unless they are possibly cinarae, which is also found in this region but is very localised.

If I saw this in France, there wouldn't be much doubt - cirsii. But there may be other Pyrgus in the location where you were and cinarae is stated to occur in the Montes Universales and the Tolman image does look very similar.

The only clue I could suggest is that the cirsii cell spot is usually wide and quite neatly rectangular, as yours is, and the cinarae cell spot in Tolman isn't. I would add that the Tolman female cirsii is shown with an almost unmarked hindwing, whereas nearly all of the female cirsii I have seen - and it is common in northern Var - have quite distinctly marked hindwings.

Tolman also says cirsii is widespread and common in Spain.

Roger

Thanks for that, Roger. Yes, cirsii is VERY common in this part of Spain. We probably saw over 500 of this species during the trip, but they usually are quite reddish on the undersides.

The markings on the ups aren't quite so bold as on these two individuals either, but realistically I'm not sure what else they could be.

I've never seen cinarae so I don't have a 'feel' for that.

Another point in favour of cirsii for the first image is the long, rather strong mark on the leading edge of the hindwing, at the end of the discal series. Male cirsii almost always has this. I've never seen cinarae myself but the pictures show a much weaker mark, or no mark, there. It's not always possible to see the leading edge but it is in this picture I took in France in 2009, showing clearly the long mark.



Guy

Thanks to David for posting this here. My photo is the second one in David's original post for this thread. Looking in Lafranchis, I would say the topside was slightly more like "cinarae" as the cell spot is pinched in the middle.

I also took two underside pictures of this individual, albeit they are "grab" shots, one blurry, one at a non-ideal angle - it was very windy and the butterfly very active!

I'm not sure what the underside shots tell me, but hopefully they may help others with better identification skills than me.

Having seen the reddish underside of "cirsii" all week, this individual definitely was much lighter underneath. It also seemed larger.

I would be very wary of drawing conclusions from a slight variation in one of the upperside markings. And in the case of cirsii, even from the underside colouring, although if it is clearly reddish this strongly points to cirsii, but the colouring is also quite variable.

Here are a selection of cirsii, nearly all taken in the same region, just to show how variable this species can be.
http://www.butterfliesoffrance.com/html ... cirsii.htm

The degree of variation in Pyrgus species makes the confident identification of them much more difficult, given that they are all very similar to start with.

However, the white markings are very clear and the cinarae images on Matt Rowlings' site (my usual reference) are very similar, so cinarae is very much in the frame. The only note of caution here, is that Paul's specimen is rather worn, and the markings on Pyrgus species tend to appear clearer and whiter with wear.

It has been said many times on these forums, but an clear underside shot would be needed in order to draw a definite conclusion.

Roger

Thanks for that, Roger, and of course I'm always mindful of how important underside images are to be certain of a positive identification with pyrgus.

I also accept too that when faded, the white markings do rather stand out more against the darker ground colour.

Without undersides, I don't think any definitive decision can be made, but given that we saw hundreds of cirsii, I believe this is the sensible, albeit default, option.

Looking like probably "cirsii" then. Thanks for the advice comments everyone