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As you say, this is a Syrphus. Locally to me, at that very early time of year, pretty much every Syrphus turns out to be S. torvus, rather than S. ribesii (which is the common summer member of the genus).
Impossible to tell from the photo, though.
My Flickr photos...
I have to admit I'm struggling to see any differences between the Syrphus species which I'm assuming are very small.
Chris Brooks - www.dragonfly-images.co.uk
My Flickr site - www.flickr.com/photos/ceb1298
They are small. Of the 3 common species, torvus has hairy eyes that you need at least a lens to sure of. The other two can be separated on the amount of black on the hind femur.
recording wildlife with The Recorder's Year on www.hbrg.org.uk/TRY.html.
Lat/Lng: 51.2, -1.0
OS grid ref: SU7451