Whilst camping in Cornwall recently we found this earthworm thrashing about in the turf. I thought nothing of it initially, but on closer inspection the poor worm was writhing about to shake off an attacker, none other than the larva of a flesh fly that had sunk it’s mouth-hook into the body of the unfortunate annelid and was rending its flesh. The earthworm squirmed and coiled, but the fly larva was in no mood to relinquish its grip and before long the struggle continued back down in to the grass with the fly larva as the probable victor.
This chance observation really goes to show how many struggles and interactions go on unseen under our noses. Typically, sarcophagid (flesh flies) larva eat decomposing animal matter, but perhaps many of them have more specific tastes, actively hunting out other animals to feed on?