Chalkhill blue with unusual marks

[sahikmet]

Today at Aston Rowant this Chalkhill blue with unusual splash of colour? Any idea what might have caused it.

[Butterflysaurus rex]

Looks like some wing damage to me, on closer inspection the scales are missing in those darker areas.

ATB

James

[David M]

This doesn't look like a natural abnormality to me, Sahikmet. I believe it's a stain that the butterfly has picked up subsequent to its emergence.

Well done though for being sufficiently sharp-eyed to both notice it AND to provide images.

[sahikmet]

Many thanks for helpful notes.