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No...the vein you are looking for is at the tip of the wing. I shall try and add an example for you.
My Flickr photos...
I've added a pic of Volucella bombylans with the re-entrant upper outer cross-vein highlighted...
It is the vein which sharply turns back to join the straight vein r4+5. Looking from the wing tip inwards, that creates an angle of less than 90 degrees where it meets. In your earlier Cheilosia, you'll see that the upper outer cross vein does not turn back where it meets r4+5, pointing slightly towards the wing tip, in fact, where it joins.
Lat/Lng: 51.43372, -2.76236
OS grid ref: ST471707