Serpulids are easily recognised by their hard and white calcareous tubes generally attached to hard substrates. They extend the feathery branchiae for breathing and for capturing food particles from the water column, but they retract very fast inside the tube when they feel in danger.

Characteristics

The Serpulidae is a family of sessile, tube-building annelids with tubes typically made from secreted calcium carbonate. They differ from other sabellid tube worms in that they have a specialized lid-like structure called operculum that closes the entrance when they withdraw into their tubes. Like sabellids, they extend the feathery branchiae, called radioles, for breathing and for capturing food particles from the water column, but they can also retract very fast inside the tube when they feel in danger. 

Recommended citation

Capa M. Serpulidae Rafinesque, 1815. www.artsdatabanken.no/Pages/313953. Downloaded <year-month-day>.