archiannelida

Meaning

A group of small, simple marine worms historically considered a distinct class of Annelida, though modern genetic analysis suggests they are likely specialized, simplified relatives of other polychaetes.

Examples

• The classification of Archiannelida has been debated by zoologists for over a century.
• Many species of Archiannelida live in the interstitial spaces between sand grains on the seafloor.