Polychaetes

Chlorocruorin main The blood of most annelid worms and some marine polychaetes use chlorocruorin to transport oxygen.

Current scientific opinion is divided between classifying them as polychaetes and regarding it as unsafe to classify them as members of any broader grouping.

Reproduction Most polychaetes have separate sexes, rather than being hermaphroditic.

Sabellastarte spectabilis Tomopteris from plankton ;Notable polychaetes * One notable polychaete, the Pompeii worm (Alvinella pompejana) is endemic to the hydrothermal vents of the Pacific Ocean.

Since the tubes had an open base, creating a single living space rather than a series of separate chambers, Cloudina is more likely to be a stem group polychaete worm, in other words an evolutionary "aunt" or "cousin" of more recent polychaetes.

Some polychaetes exhibit remarkable reproductive strategies.

The Polychaeta or polychaetes are a paraphyletic class of annelid worms, generally marine.