Observed sunny day, mid morning in a small town garden.. Not sure if it is possible to differentiaite between S. ribesii and S. vitripennis.
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It's generally considered best not to try to do Syrphus to species from a photo. You can be pretty sure that this is not vitripennis, which has much black on the hind femora. It is probably ribesii, with yellow hind femora, but there are torvus and rectus to consider, too, and they are variable in the extent of their markings. To be certain, you need to see the presence or absence of eye hairs and of microtrichia (tiny hairs) on the basal wing cells (and that just can't be seen).
Probably ribesii, then, but can't be sure.
My Flickr photos...
Many thanks ophrys for your guidance
Lat/Lng: 51.5697, -3.2269
OS grid ref: ST150863