So it is with these black and yellow wasp mimic hoverflies. Some have four black rings (or stripes depending on your point of view!) but the one in my photograph has five so this is either Syrphus ribesii, Syrphus vitripennis or Syrphus torvus. Which of the three? There is no way of knowing without looking at detail such as whether the eyes are hairy or bare and whether the hairs on the femur are purely yellow or have black hairs amongst them. So my record has to be listed purely as Syrphus species!
Read more: Hoverfly: Syrphus species | Nature Notes from Dorset