Neanthes virens, also known as clam worm, is an annelid worm that burrows in wet sand and mud. It is classified as a polychaete in the family Nereididae. Sandworms make up a large part of the live sea-bait industry and have many distinctive traits, including often reaching great length, sometimes exceeding four feet; numerous, highly vascularized parapodia along both sides of their bodies; blue heads with two large pincer teeth.