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Hi there, today I found this dead fly on a window. Looks like still alive but is real dead. What is the white around there? Where does it came from? Spewed, don't think so? Burst out, don't think so? Done by eating enemy, don't think so? Any idea? What species is it, I think a syrphidae? By the way, its still there on the window ;)
Seen in SW-Germany, Baden-Württemberg, region Heilbronn, today 25. August 2017.
Thanks in advance,
Norbert
edit: size about 10mm or a bit less. It's a female?