I was fortunate enough to see two of these beeflies having a battle. It is a large beefly with strong vein markings on the wings. I heard the two males (I presume) first and they were flying and crashing into each other. One sat down for a little while allowing me to move in for a couple of photos before he buzzed off very fast. I notice he has damage on both wings.
Comptosia aurescens ID with thanks Michael Jefferies. See Michael's comment on
www.flickr.com/photos/jean_hort/16228974915/