from what I have seen and read, mantis don't burrow as much as a pistol. I have kept about a half dozen pistols over the years, and each and every one has made LOTs of burrows - every night.
I think the pistols look for food in the sand, and the mantis hunt the bigger stuff like your fish and fingers.
All Pistol shrimp look like little lobsters, but in all sorts of colors and one claw a little bigger than the other and with a funny knob. Mantis dont, they look like......mantis shrimp, so if you catch him at night, you should be able to tell the difference.
Oh yeah, and if you wake up in the morning and the tank is shattered on the floor and/or all your fish are missing, you had a mantis.