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What type of Clouded Yellow is this???.. taken first week in July, 100k south of Lyon in Rhone valley

I'd say it's either a male Pale Clouded Yellow (hyale) or a male Berger's Clouded Yellow (alfacariensis).

I say this because the dark patches on the forewing upperside can be seen running outside the line of dots on the underside. In Clouded Yellow, they head towards the line of dots, but then come back inside the line. I hope that makes sense!

Cheers,

- Pete

I agree. To say more than that from the picture alone would also be very brave, because although on average there are visible differences between pale clouded and Berger's, there is huge overlap and most people agree they cannot be separated confidently from the underside alone.

However, there are habitat clues. Berger's is more sedentary and almost invariably associated with horseshoe vetch in calcarious habitat. Pale clouded has a wider range of foodplants and habitats. Thus, if you are on a chalky hillside with horseshoe vetch there is a presumption of Berger's (though it might be pale clouded). Elsewhere, there is probably a presumption of pale clouded.

For what it's worth, your butterfly looks more like pale clouded to me, though that's almost just a guess. Here's a couple of photos I took this year, the first pale clouded and the second Berger's for comparison:




I am certain the second one is Berger's but the first one is not quite so definite - I saw the upperside of the hindwing through the underside against the light and its extent strongly suggested pale clouded. Here is this view:



Guy

Thanks,

had it filed in my colias folder.... I really must improve my recognition skills

No shame, Paul!!! I gave up expecting to be able in general to separate these two long ago. I refer to them together as hyalensis (hyale + alfacariensis) and very often leave it at that...

Guy