Bee ID Please

Can anyone help identify this bee? It's the only one like this I've seen in the garden this year. What really struck me was the black body and enormous eyes. Not a great pic I'm afraid as it flew off before before I could get the camera set up properly.
My best guess so far is a leaf cutter, but the eyes seem larger than in the photos I've seen on the web.
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Hi Dave,it's actually an hover fly Leucozona lucorum a bulky hover with a 25mm wingspan.

 

Thanks Walnut I thought you might just come up trumps.
I'd an idea that it might be a hover fly when I saw the large hover fly shaped eyes but I'd never seen one that size before.