I'm not sure what this Damselfly is but looking at my Collins Insect Guide I think it could be Demoiselle Agrion, definitely not a Banded Demoiselle from the lack of bands on it's wings.
The extra is how Luna spent the afternoon whilst I was busy cutting the grass and trying to evict Ants from my bag of compost, I don't think I ever will !!
Luna did condescend from time to time to check that I was OK and still working whilst she was busy checking out the movements of the Water Vole, Moorhens and male Mallard.    At least she was in the shade and there was a cooling breeze from the river.