Yes, it looks like it ready to pounce! It kinda looks like the predator from the movie Predator, with those beady eyes and patchy coloured head..
I bought it as a "emerald crab", but the "emeraldness" begins and finishes with the crab being green...then again I also bought a peppermint shrimp from the same store and it wasn't really as advertised either.
Now, I know better than to buy from anywhere other than RC...
The trick will be getting the bugger out without loosing my rockwork or a finger..