Image Gallery: Polychaetes
Polychaetes are the most diverse and abundant of the worm groups. Originally classified within the Phylum Annelida, together with the earth-worms (Class Oligochaeta) and the leeches (Class Hirudinea), recent studies have failed to show that the annelids are a monophyletic group.
This means that currently, the term ‘polychaetes’ should be used, rather than ‘Annelida’. Polychaetes now include all the traditional polychaete families as well as the leeches, earthworms, and the siboglinids, sometimes known as ‘beard worms’.