The Sucker

Far away, it looks like a grey bent gravel. But actually it is a wet slimy living thing wriggling straight on the wet floor. When disturbs, it just pretends to be dead gravel and bent, motionless.

When it was turned over, it appeared that it had sucker like the lizard's foot, except that the middle was slimy, helping it to move steadily on the floor and the wall. Perhaps,the slime helps the fellow to glide on the floor! It is like a worm, I cannot see other features.