Canalipalpata

Canalipalpata, also known as bristle-footed annelids or fan-head worms, is an order of polychaete worms consisting of 31 families such as the Serpulidae (tubeworms), Sabellidae (fanworms and feather duster worms), and Siboglinidae (beardworms) of the suborder Sabellida, and the Alvinellidae, a family of worms often associated with hydrothermal vents (though a number of Siboglinids also inhabit hydrothermal vents, like the giant tube worm Riftia pachyptila). Most canalipalpatans are considered to be tube worms, with some exceptions.