First Death??? Not Sure...

[pyro]

Welllll, I came home from school today to find one of my two emerald crabs not moving in the bottom front center of my tank. I poked him with a plastic stick (I know, very technical), and he didn't move, just sortof rolled. This might sound sortof wierd, but his legs didn't fall off and he wasn't soft. Do crabs go into a "rigor mortus" stage? He wasn't there yesterday. He has been missing 3 of his legs on one side, missing the top half of one of his chelipeds, and had about a 1/8" hole in his shell since I bought him about a month or so ago. Could he just be molting?
I noticed his eyes were redish tinted.
Well, I think I've had my first death in the 4-5 months or so my tank has been setup for. Ohh well.
Was it's prior injuries just like a time bomb? The other one still appears to be doing great. Any idea's on how it might have died?
EDIT - water params are great, constant (I beleive) 81F, 0 NH3, NO2, NO3, pH of 8.2

 

[cayman isl]

There is the possibility he has molted... you can check the shell and see if the "trap door" is open on the back. He may have left and is hiding until his new shell gets stronger..
If you do a search on emerald crab molting there may still be some pictures of what the trap door looks like... I think Kip had posted a pic a couple of years ago..

 

[pyro]

...It's not like I'm personally scared of dead animals - I just split my fetal pigs jaw open in anatomy today... but, nevertheless...
Is there anyway to tell without pulling it out and playing with it? The thing felt relativily too heavy for just a shell when I poked it with the stick and with my luck i'll play with it and dead crab meat will fall on my lap.

 

[pyro]

sorry, anybody?