Colonial Sand Castle Worms (Phragmatopoma californica)

Contributed by Dr. Bonnie Becker

Where found:  Found in the high to middle intertidal on the sides of rocks, often competing for space with mussels. Often seen on overhanging ledges and concave shorelines.

Interesting facts:  Their tubes are made from sand that has been cemented together.

Adaptations:  The worm lives in the tube and is rarely seen without destroying the tube first. The animal has an operculum that seals up the tube with the worm inside it during low tide.

Food:  During high tide, the worm extends lavender tentacles, which gather food particles from the water.

Life history:  Large colonies formed not by cloning (asexual division) but from the settlement of individual larvae. The larvae use adult worms as a settlement cue, thereby adding to the colonies.

Classification:  
Phylum:           Annelida (Segmented worms)
Class:              Polychaeta (Bristle worms, Fan worms, Clam worms, etc.)
Order:             Terebellida
Family:            Sabellariidae

Last revised 13-Jun-13