Eunice Aphroditois, The Bobbit Worm

Eunice aphroditois, the Bobbit worm, is an aquatic predatory polychaete worm dwelling at the ocean floor.
This organism buries its long body into an ocean bed composed of gravel, mud or corals, where it waits patiently for outside stimulus to reach one of its five antennae.
Armed with sharp teeth, it is known to attack with such speeds that its prey is sometimes sliced in half. Although the worm hunts for food, it is omnivorous. It is also covered in bristles that are capable of a sting that results in permanent numbness in humans.