Blue legged hermit crab...multiplied?!

[Stacyvamp]

This is totally going to sound weird, but I bought two blue legged hermit crabs, yesterday, and today, I see a third one, without a shell? It looks like it’s molting, from what I’ve read online. This is my first time having these creatures, so I have no idea what’s going on. I attached two photos, Both shells are taken up with the crabs that I bought, but next to the second shell, there is a pair of blue legs and white meaty substance..... I put it next to the shell but it was originally found this morning under a rock....
Someone please explain how this is possible? I double checked, both shells are indeed taken up by the crabs, I can see their legs sticking out and they are moving. So where did this third one come from? and what do i do with it since it doesn't have a shell

 

[Waterbabe]

From what I can remember molts do not have eyes... double check for that first. You got them yesterday? May be a little sign of stress if he left the shell? Or he could of molted, usually done on sand. They can stress a little if they are not happy with shells available, we used to put a few extra shells in as they sometimes move home for a nice change, or even kick each other out of there home to pinch it! See if its alive first and not just molted if you can.

 

[Donya]

If both shells have crabs and you only got 2, the mystery "crab" is a shed skin from one crab, which gets cast away and will blow about in the water since it's hollow. You can remove it or leave it in for them or other clean-up animals to eat. I don't see anything abnormal looking that would make me think it's a previously hidden 3rd crab that died - the back of the hermit crab is a big, soft, almost worm-looking thing with weird little legs on it and that part is not part of a shed skin - but it too also sheds a thin, wispy outer skin layer. When a dead crab first falls out of its shell the soft body will be intact although it will rapidly get eaten by other animals.

Occasionally, if the molt doesn't go well, legs can get stuck inside the shed skin and left behind and that will definitely look meaty - but the crab itself will make this obvious by not having all its legs intact post-molt.