I think this is one of the Merodon sp flies? Might it be M.equestris?
No interactions present.
There is only the one species of Merodon in Britain, though there are many more on the continent.
My Flickr photos...
Thank you for that info. I noticed that there were several forms, but played safe and didn't attempt to choose one.
Lat/Lng: 51.3, -0.1
OS grid ref: TQ3468