One of my favourite hoverflies, and I got a nice shot of this male.
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I agree, but for the reason that the yellow lunules do not meet up with the margin of the abdomen, so that the margin is black all along. There are other species where they do not meet up in the middle, like corollae.
My Flickr photos...
Sorry - by the midline, I meant the middle of the side of the abdomen; it's the midline when seen from the side. So I was trying to say the same thing as you.
It's amazing how hairy some insects are, when seen close up, even if they look smooth and shiny from even a short distance.
Lat/Lng: 51.3685, 0.0115
OS grid ref: TQ401651