Not to worry, these are the pet variety. My son wanted a per of his own and somehow ended up with two hermit crabs, names Lightning and Flash.
Unfortunately, on day two, Flash burrowed into the sand of the "crabitat" and has rarely been seen since in three weeks. Lightnigh on the other hand, can often be found climbing the plastic vines we provided.
The third photo shows a "naked" one running around, but we don't know who it was, as the other was dug in, and can only tell them apart by shell colour!