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I think this is not E. horticola - the wing shading is inadequate. My instincts go with E. arbustorum but I fear that the resolution and angle are inadequate to be definitive. Thus Ian is right - the best one can say is Eristalis sp.
No thats cool it was only a guess by me form my limited id book
Lat/Lng: 52.2, 0.1
OS grid ref: TL4660