Ant, no common name
I'm not sure what made me give this ant a second look. But, it didn't look quite right for the common black garden ant, Lasius niger. So I took its picture and sought advice.
Back came expert opinion that it was a wingless queen Lasius umbratus (it is just possible to see the scars where the wings were attached to the thorax, just behind the front legs). Since this species spends almost all of its life underground at the base of old trees and stumps, it is rarely seen.
Mating takes place in September and the queens then fly off, lose their wings and search for suitable new nest sites. So the opportunity to see them is quite short.
The new colonies will be set up in the nests of other Lasius species ants found around suitable tree stumps and boulders.
Found 15m from old chestnut trees and a pile of fallen branches.