Keelworm Pomatoceros triqueter

Keelworm (Pomatoceros triqueter)

Meadfoot Beach, Torquay, Devon. August 2015. © Peter Hillman

Family Serpulidae (Serpulids)

Tube width 3-5mm.
Worm length up to 25mm.

The tube in which the worm hides at low tide is white and smooth, irregularly curved, hard and calcareous with a single prominent ridge along its back. It looks triangular in cross-section. The worm itself is small with varied colouration,  and has a crown of feeding tentacles. Similar to Pomatoceros lamarcki which has two ridges each side as well as a centre ridge.

Found encrusting and scarring rocks and shells on the middle to lower shore. Discovered on most types of coastline. Common and widespread.