Spectacular, Karl. These almost look like mirror images of each other. Good job getting both in focus (I can't get even one of these to sit still for me). Nice background too - though I would clone out the distracting white area in the lower right corner.
Nice job capturing this quick guys! I agree with Steve that the LR white is distracting. I'd also consider cropping a little off the right only (keep the rest of the frame as is), to take away some of the balance in the frame. It would give a different mood, changing the feeling from a meeting or conversation of the flies to a tug of war for the stem.
Agree with the others - my feeling on this is also that it would have made a nice vertical crop if you had more stem down below. As is, I feel like it got chopped because it is wider than it is tall. Still, what a neat image and the BG is so perfect with this, fitting the light tonal range and blending right in.
Lose that white at the bottom and you've got a great photo!