One of my innumerable Bizarre Monster Pics, tagged the 'gnasher' for fairly obvious reasons. Yes, it has a three-part lower jaw. Do I know why? No, aside from possibly a bigger gape. Eyes? Who needs 'em!
...wow. That is really nicely done, and i do like the three-jaw idea, tho I'm not entirely sure how that would work. But it's gorgeous as a drawing, and very... awe-inspiring. Yet another thing to add to the list of "Things you'd never want to meet in a dark alley..."