Glass-winged Syrphus Syrphus vitripennis

This is one of those common species of hoverfly that I'm surprised I hadn't recorded before. This one came to light and was identified mainly by the extensive clear area in the second basal cell. The minimal extent of yellow on the hind femur also supported this ID though the hairs in this yellow area looked mainly dark which they're not supposed to be*.

*I've since looked at Bot and Van de Meutter and this clarifies the precise position where the yellow hairs should be: black hairs through most of the yellow region of the femur are fine, it's just at the upperside of the apex where they should be yellow (I can't tell from the photo if there were any yellow hairs present here or not).

male Glass-winged Syrphus Syrphus vitripennis showing squama, hind femur and wing (with increasing zooms to show second basal cell detail), Wendling Beck Environment Project (Norfolk, UK), 26th July 2025