These seemed very choosy about where to rest - the vast majority were on lily-pads.
No interactions present.
The Small Red-eyed Damselfly, Erythromma viridulum is very similar - with the most obvious difference being more extensive blue towards the tip of the abdomen.
I was fairly confident of the identification, but the species is a new one for me. The various Odonata at Woodwalton are some compensation for my forced move to the south-east!
The south-east isn't that bad, I'm sure that you'll get used to it.
Look out Small Red-eyed a bit later in the year!
Lat/Lng: 52.4515, -0.1889
OS grid ref: TL231852