There are a few ‘be careful with this’ and ‘avoid doing that’ in the marine hobby. Some are born of experience, occasionally painful, and others of practicality.
Most marine aquarists are aware of the mantis shrimp. They come in two models, the ‘clubbers’ who bash their victims and the ‘spearers’ who, well, spear them. They can also grow large – I believe the biggest ones can grow to 40″ (circa 101.5 cm).
Have a look at the video that has been uploaded in the Social/Forum area (just go to the area and then click on Videos). There are two about mantis shrimps, the one relevant here is “Watch Those Fingers”…
This is a sizeable mantis being handled in a very carefree fashion. The mantis is incredibly tolerant! Maybe the aquarist has had it a long time and knows exactly what the shrimp will do…he hopes!