Considered one of the most diverse assemblages in the fossil record, the marine polychaete worms of Mazon Creek were large, predacious, and free swimming. This contrasts present-day marine polychaetes, which are generally small, sedentary, and deposit- or suspension- feeders. The polychaete body is a cylinder of muscles in segmented units. Chitinous bristles (chaetae) are secreted by the epidermis and adorn the body and extensions of the segments. Today, Polychaetes as a class are robust, with over 10,000 described species, and widespread in every type of ocean habitat.
1. Mazopherusa prinosi, commonly called the Fan Worm, is considered a colonial animal and rather sluggish. While fan worms rest in their burrows, they extend their fans to create eddies causing detritus to fall into their mouths.