|This, I believe, is a Giant Isopod. I don't know for certain as I had to hunt around on google at deep sea creatures, to find one that looked like it - so if anyone can prove me wrong, please feel free to!
Taken from wikipedia:
Maturing to a length between 19 and 37 centimetres (7.5 and 15 in), and maximally reaching a weight of approximately 1.7 kilograms (3.7 lb) in B. giganteus, giant isopods are a good example of deep-sea gigantism (cf. giant squid); most other isopods range in size from 1 to 5 centimetres (0.39 to 2.0 in). Their morphology is nonetheless familiar to most people as giant isopods closely resemble their terrestrial cousin, the woodlouse: their bodies are dorso-ventrally compressed, protected by a rigid, calcareous exoskeleton composed of imbricate segments. Like the woodlouse, they also possess the ability to curl up into a "ball", where only the tough shell is exposed. This provides protection.
Canon EOS 5D
Flash: Not Fired