end0skeletal:

Eulagisca gigantea, the giant polynoid worm, is a species of marine Polychaete worm belonging to the family Polynoidae, the scale worms. This species is found on the seabed in the Antarctic Ocean. It grows to around eight inches long, and judging by the jaws, it is a predator, but little is known about its diet or behavior.

The area that appears to be the head is actually a retractable pharynx; the last photo shows what it looks like when the pharynx is retracted. (x x)