It’s like something out of ‘Alien’

Can anyone help us identify this horrible creepy crawly, which almost makes this angler jump out of his skin? We found and reposted it on GooglePlus, then traced it to to Imgur but that’s pretty much where the trail went cold. It was clearly made on, but that doesn’t have a very user-friendly search tool and we can’t find the original on Youtube. Can you help?

What is the alien invader that comes out of the fish’s mouth??

Alien invader

Edit: since posting this I’ve heard people suggest it’s Cymothoa exigua, but it moves so fast I can’t believe that’s what it is?!

James Green About James Green

James Green loves nothing more than casting a fly in pursuit of salmon, seatrout or, when the opportunity arises, a tailing bonefish, tarpon or permit.