Keelworm Pomatoceros triqueter

Keelworm (Pomatoceros triqueter)

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

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.

Common and widespread on all coasts.

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

When to see it
All year round.

Where to see it
Encrusting and scarring rocks and shells on the middle to lower shore. Discovered on most types of coastline.

Polychaeta (Bristleworms)


Serpulidae (Serpulids)