Sabellidae, or feather duster worms, are a family of marine polychaete tube worms characterized by protruding feathery branchiae. Sabellids build tubes out of a tough, parchment -like exudate, strengthened with sand and bits of shell. Unlike the other sabellids, the genus Glomerula secretes a tube of calcium carbonate instead.

Feather-duster worms are comparatively large segmented sedentary marine tube worms. Its common name of 'feather duster' refers to its giant size fan-like colored crown tentacles situated on each side of its head.

feather-duster worm, any large, segmented marine worm of the family Sabellidae (class Polychaeta, phylum Annelida). The name is also occasionally applied to members of the closely related polychaete family Serpulidae.

Sabellids live in long tubes constructed of mud or sand cemented by mucus, whereas serpulids build tubes of calcareous materials. The epithet feather-duster refers to the multicoloured crown of finely divided tentacles that are attached in two groups, one on either side of the worm’s head.

Fan Worms Feather Dusters look like a cluster of feathers sticking out of a tube. A worm creates this soft, flexible tube around its body for protection. The feathery part that sticks out of the tube is called the crown or fan, and at its base is the worm’s mouth.