Merpugs

Merpugs - they exist!  What?  You've never heard of merpugs?  Hmm, well it might be because they stay close to the ocean floor.  Their weight naturally keeps them down and so they only move around if they exert effort, and that isn't often.  And they tend to spend most of their time eating and sleeping soooo...  Hmm, no wonder merpugs are such rare sightings!