www.ukbutterflies.co.uk

I took the attached picture at Arnside Knott yesterday. I can't decide whether it is a Dark Green or a High Brown and I didn't see the underside. Any suggestions?

David

I would plump for High Brown.
High Brown have the lower section of the margin of the forewing either straight or slightly concave, whereas the Dark Green is invariably convex.
But, I stand to be corrected.
Roger Harding

I agree entirely. The wing shape is a very useful feature and in this case is absolutely clear. Abroad, Niobe fritillary has a straight or convex margin, like dark green, and so the slightly concave wings of high brown are particularly helpful to know about.

The postdiscal spots on the forewings are also characteristic. In dark green they are pretty well parallel to the outer margin, while in high brown they take a bend at the third from the top, which is generally quite small.

Guy

Thanks to you both. I am now looking through my other photographs taken at Arnside to see if they are are all High Browns.

David

I found this one among my photographs. It was taken on a different part of the Knott. The postdiscal spots on the forewings seem to be more in line. Is this a Dark Green?

David

Yes - I'd say Dark Green for this chap.

Cheers,

- Pete

Thanks Pete,

I'm pleased I managed to se both High Brown and Dark Green on the same day at the same site.

David

You've got me going now. I was pretty sure this was a dark green since it was seen in open heathland.
Thanks in advance for comments.

I'd "side" in favour of Dark Green, but this critter is borderline (to me) in terms of both spots and wing shape. What site was it at?

Cheers,

- Pete

Thanks for the comments, Pete. It was at Priddy Mineries in Somerset. There is woodland about half a mile away but it's largely coniferous and, as far as I know, doesn't support any fritillary species.
This individual was nectaring off clover along the main pathway along with maybe half a dozen others. I got a good look at the underside of at least one of these and these at least were definitely DGF. The habitat is typical for DGF with gorse, heather and long grass although there are large marshy areas too.
Incidently, earlier in the year there were marsh and small pearl bordered fritillaries here.