Lovely shot. The dappled light works really well here. I don't know what one could do about the bleached-out flower at the left--bit of bad luck there.
Hi Stuart, I like the detail in the butterfly's body and the light on the wings plays out nicely. I find the BG a tad busy but overall this is nicely done. The flower on the left as Ron mentions does tend to draw my eye.
The butterfly gave you a very nice pose and you have excellent sharpness within your DOF! I also like the comp and the interesting lighting on the butterfly. Very well done!