Honduran sea monster in Roatán, Honduras

I took this video of an unidentified sea creature in Roatán, Honduras, on the West End Divers dock at sunset, about three weeks ago. I asked around the dive shop, but nobody could identify the creature. West End Divers suggested I visit Reef Gliders and ask Mickey, who knows the sea life of Roatán better than anyone. But even he wasn't quite sure.

My friend Sean thinks it may be a parasite that recently left its host.

I think it's at least one meter long.