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The presence of a shimmer stripe separates this species from C. flavipes, but not from C. ceriaeformis or C. strigatus. This is a male, and ceriaeformis would have less black on the tergites, while strigatus has extensive black markings on the face. This species is common at the moment, and conopid flies generally are worth looking out for on thistles, Ragwort, Upright Hedge Parsley and other flowers...I had 5 different species on Water Mint, this morning.
My Flickr photos...
The first one I have seen I think, and fortunately this one was very amenable to close up photography. I wasn't sure which species but saw images of C.ceriaeformis which looked very similar in abdominal black banding and the red marking on top of the head.
This key is useful, though it includes European species, too...
quadrifasciatus and flavipes are the two common species.
Lat/Lng: 53.2432, -1.9108
OS grid ref: SK060718