I am pretty sure it is an Iridescent Shark. I got it today, for free, from a woman who wasn't sure what it was. She just knew at 8-9", it was too big for her 20 long.
I have in a 50 by himself, until I can find him a home. It's a good looking fish, I just don't have the tank space for him. Anybody in the Philly area want him. I can also bring him to East Brunswick NJ.