Common flesh fly, Heeswijk-Dinther, Netherlands

Named "checkerboard fly" in dutch, in reference to its pattern. Which makes little sense, because it is more striped than checkered. Larvae exclusively feed on rain worms. Eggs are deposited at entrance or exit points, once hatched, the larvae will find their own way to the rain worm, enter its body and ultimately kill it. The process is rapid, the larvae are already fully grown after a few days.