Like Doug, I could imagine this to be a crab-like sea creature.
To create the creature, I deleted the white background and used the liquify filter to give the "sea creature" a slight spiral. Then used the 3d transform filter to rotate it spherically onto it's "belly". I painted in a crab like carapace, added a drop shadow and it was done.
I set the creature on a sea bed, adjusted the hue to be a little more blue since we are looking through water, and applied a medium ripple filter.
This is my first challenge post. Hope you enjoy it.