Several, see text Terebellida make up an order of the Polychaeta class, commonly referred to as "bristle worms".

Together with the Sabellida, the Spionida and some enigmatic families of unclear taxonomic relationship (e.g. the Saccocirridae), they make up the subclass Canalipalpata, one of the three main clades of polychaetes.

[1] Cladistic studies have hitherto only analyzed a rather small proportion of polychaetes; hence it may be that some of the families today included in Terebellida by most authors will eventually be again recognized to belong elsewhere.

However, as the terebellid habit of constructing characteristic tubes in which to live seems quite ancient, such structures are occasionally found in conservation Lagerstätten.

[citation needed] Prehistoric polychaete genera historically presumed to be Terebellida include the following, though most are now recognized as trace fossils of uncertain makers: