Having looked into it further...Without wanting to appear to be a doubting Thomas - thats Bo!!ox
Only two creatures with pharyngeal jaws of the type in question...
1) Moray eels
2) The Alien
Q: Which came first?
A; Moray eel
Where did Ridley Scott and HR Giger get the idea for the Alien's pharyngeal jaws?
If I was a moray eel and watched 'Alien', I'd be studying the credits for mention of where the pharyngeal jaws came from and be on the phone to my lawyer...