* Ribbon worm (Cerebratulus lacteus): This species is found in the intertidal zone of the Pacific and Atlantic Oceans and can reach lengths of up to 1 m (3.3 ft).
* Bobbit worm (Eunice aphroditois): This species is found in the Indo-Pacific Ocean and can reach lengths of up to 3 m (9.8 ft). It is a voracious predator and has been known to attack and kill fish, octopuses, and even small sharks.
* Green ribbon worm (Prosthiostomum siphunculus): This species is found in the Mediterranean Sea and can reach lengths of up to 10 cm (4 in).
* Yellow ribbon worm (Prostoma obscurum): This species is found in the North Atlantic Ocean and can reach lengths of up to 15 cm (6 in).