Toronto, Southern Ontario, Ontario, Canada September 9, 2009
I saw the caterpillar first, then noticed a fly hanging around "suspiciously", first thinking it was a housefly. It stayed to the rear of the caterpillar most of the time, then eventually approached it from the side, curling it's abdomen underneath itself. I then recalled reading that Tachnid flies parasitize caterpillars and figured this is what I was observing. Couldn't get as may good shots as I wanted, but here are 2 that seem to show what's going in.
Contributed by Michael Battenberg on 10 September, 2009 - 6:13am Last updated 5 December, 2009 - 10:06am
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