A chequered fly

This is a backblip for Sunday as I was still up a ladder, stripping (damned) woodchip paper from walls. In a brief lunchbreak spot of fresh air in the garden, and in glorious sunshine, I photographed this specimen of a hoverfly species I've been thinking of all summer as 'the tiny, black, shiny one'. It was taking nectar from a range of flowers including, here, red campion. I haven't managed to identify this species previously which is frustrating as it seems like one of the commonest hoverfly species around here. Then today, I had a flash of inspiration. I think it is the Chequered Hoverfly, Melanostoma scalare, a very widespread and common species in most of Britain. No doubt Craig at Buglife may correct me a propos of improving my sketchy insect knowledge but I'm quite confident about this one!