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a fly 12mm exactly including eyes, 10mm abdomen. Sitting with large marmalade flies, I thought it was an extra large one, but the abdomen is long and thin, and when I caught it in a tube it looked like a tiny dragonfly, a long narrow body swollen at the end, with an odd squared-'Y'-shape appendage sticking out the end like a short, wide tuning fork. Blueish oblique shapes on the latter sternites, some slight dark orange markings along the tergites
What family might it be?
regards, Jeremy