Ancestor of arthropods had the mouth of a penis worm

Imagine a meter long worm with 12 stubby legs and matching sets of flaps running down the body. On the head is a large pair of spiny appendages used for grasping prey that transport victims into a circular mouth with several rows of teeth. For years, scientists have disagreed over whether this mouth belonged to the Anomalocaris, the largest sea predator from the Cambrian Period, or was comparable to the penis worm, a subset of priapulids, a category of marine worms that were diverse in the Cambrian.
Strange & Offbeat: Fossils & Ruins News — ScienceDaily