Ottoia

Ottoia (named after Otto Pass, British Columbia) is a stem-group priapulid worm of the Middle Cambrian period found in North America and Europe.

Description
Ottoia was similar to modern-day priapulid worms in morphology. For example, the spiny proboscis distinctive of this phylum is present at the front end of the animal. Specimens measure an average of 8 centimeters long, although they can range anywhere from 3 to 15 centimeters.

Classification
Although Ottoia was a type of priapulid worm, it has been given its own taxonomic family, Ottoiidae.

Distribution
Ottoia fossils are prevalent at the Burgess Shale fossil site of British Columbia, with over a thousand specimens known. In addition, it is also known from deposits of the Wheeler Shale in Utah, as well as sites in Spain and Nevada.

Paleobiology
Ottoia was a burrower, and an active predator. It is believed to have constructed U-shaped burrows in the sea substrate and waited for a potential prey item to approach, whereupon it would grab it with its flexible proboscis. Fossil evidence, including gut contents of Ottoia, support this theory, and it is even possible to tell what genera it fed on.