Hoverfly in the garden last month. I just got around the identifying this and quite by chance I believe I have the key photo (pic 2).
No interactions present.
here's one example of a deceptive viewing angle
as you can see, the leg needs to be turned in order for the black to become obvious
latest pics and diptera videos
Lat/Lng: 51.072, -0.69
OS grid ref: SU918311
In my garden, in mixed broadleaved woodland, altitude 238m, oak, birch, chestnut and willow nearby.