What would be the scientific name of this worm
If you would have read the text from the source of that image (which by the way you didn't mention, I did a Google Image search and edited your question to include it), you would have known that what is seen in the picture is not a living thing, it is a latex fishing lure:


  Product Description: Sandworm/Ragworm 8″ size, sure fire fish catching lures. Costing less than live worms, but lasting much longer, never be without worms again. 


Source: http://www.seafishingtackle4u.com/softbaits/ragworms-latex-lures/