Out of interest, what was the flash setup for this?
This was a simple (read: I was in a hurry because I didn't know how long the mantis would hang around in the yard) setup. Just the MT-24EX mounted via it's included mounting ring, directly on the end of the MP-E 65mm lens. The shot was handheld.
I do have an RRS macro rail setup, and for the MT-24EX, I often use a pair of Wimberley F-2 brackets for the heads, which allows more flexibility in positioning the heads. I also sometimes use a 600EX-RT on an RRS bracket with an extension, to light the background (optically slaved to the MT-24EX as master).
Here's that rig set up with the 100L: