Framed Moray eel (Gymnothorax pictus) skull with its Pharyngeal jaw. This species is found in tropical marine waters of the Indo-Pacific region.
As "Alien" as it gets, these eels have a second jaw deep inside their throat that is actually projected forward to grab what the eel has bitten with its primary jaws. The primary jaws then let go, and the Pharyngeal jaw then pulls the item down the throat. Make sure you look at the xray image as well.