"Alien" is nothing compared to this horror story told by Lost over at CDL:
"This demonic denizen of the deep are a type of Barnacle that hunt down and turns [the crabs] into zombies! They attach to a crab at its joint and then works its way through the shell. Once inside, they extend their foul tenicles through out the crabs body and completely take over the crabs digestive, reproductive and neuro systems. From here is sucks all the nutrients it needs from gut of the crab while preventing from growing or leaving its shell. This causes the crab to no longer be able to grow or regenerate lost claws."
If this the crab is male the Sacculina barnacle will feminize the crab, making it take on the appearance of a female crab.
More here!
