Munching.....

.....its way through my lemon tree.
Just when you thought there couldn't be anything else to thwart my gardening activities I found this today. I decided it would make a blip and then noticed it wasn't alone. 
A Google search identifies it as a Papilio aegeus or Orchard or Citrus Swallowtail Butterfly. Apparently it turns into "one of the largest butterflies to grace suburban gardens", but that doesn't help my lemon crop.