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Can anybody help me to determine these caterpillars?

Nickerl's Fritillary?
Nickerl's Fritillary?

This caterpillar was snapped on the Hemp Agrimony near the forest road but I am not sure if it is its foodplant. Probably it is some arctiid. Other photos of one are here:
photo2
photo3
photo4

And I am not sure if I have correctly determined this fritillary ( and another photo of one) as Dark Green Fritillary - Argynnis aglaja.

Hi Traplican,

The fritillary is selene - the round spot at the base of the hindwing indicates Clossiana and the rest of the pattern indicates selene.

As for the fritillary caterpillar, I'm not sure. I'm no expert on caterpillars, but my first impression was didyma. Looking in my books, I find the white spotting too prominent for aurelia or its close relatives. It also looks good for diamina, but the foodplant is wrong - didyma takes a range of fooplants. Normally, the projections on didyma look more orange, but the lighting in your picture might disguise this. Maybe someone else will have a better idea.

Guy

Here is a didyma caterpillar I photographed yesterday, on Linaria vulgaris:

Thank you, Guy.

I just have obtained message from Jiří Beneš: The fritillary caterpillar is M. athalia and the hirsute caterpillar is Arctia caja.

I have uncorrectly determinated the Pyrgus on the photos 10606 161 and later; it is not Pyrgus serratulae but P. carthami.

JJ

I can understand why you identified the Pyrgus as serratulae, but I agree, it is not that. On the other hand, it is very difficult from those views and markings to make an accurate determination. Was it because of the foodplant? I can believe carthami, but would not have been able to identify it on those views alone.

Here in Switzerland carthami flies with serratulae so we get good opportunities to compare them. In fact, they are entirely different butterflies. Above all, they are quite distinct in flight. Carthami is huge and bouncy - instantly identifiable without even looking at the markings. Serratulae is much smaller and more 'ordinary'. Photos don't show this obvious difference. Here are serratulae (behind) and carthami (in front) photographed this last weekend - they look surprisingly similar, even though there is no possibility of confusion in the field:



Guy

padfield wrote:I can understand why you identified the Pyrgus as serratulae, but I agree, it is not that. On the other hand, it is very difficult from those views and markings to make an accurate determination. Was it because of the foodplant?

Yes, it was. Czech name of Pyrgus serratulae is soumračník mochnový after mochna - cinquefoil and when I saw the female putting egs to the cinquefoil the first my thing was that it is this species. I sent the message about this find to the Czech Entomological Institute and it was redeterminded by Jiří Beneš as Pyrgus carthami. Its foodplant is cinquefoil, too, and it was very large skipper.

I watched a female carthami today at her breeding site. She was indeed laying on cinqfoil, pressing eggs under the leaves, and I was able to get shots of an egg:





The plant:



Guy

Very nice photos, Guy! I hope I shall sometimes shot similar.