Lagis koreni

[3] It lives inside a long, narrow, conical tube composed of a single layer of grains of sand and shell fragments, skilfully cemented together like a mosaic [4] with a biomineralized adhesive substance secreted by specialized glands.

After processing the mineral grains and organic matter, unconsolidated faeces are ejected at the posterior, narrow end of the tube and are deposited on the sea floor.

In some fine-grained sediment, the worm also forms a burrow up to the surface from its feeding cavern, actively keeping it open.

Any nutritive benefit to the worm of this practice probably depends on the assimilation of organic molecules and microbes adhering to the surface of the pellet or soluble components from inside.

In a study off the coast of Wales, the worm released sperm in bundles into the water column in May and the ova matured at the same time.

[7] The trumpet worm is sometimes found at a density of a thousand individuals per square metre, but numbers fluctuate greatly.

Species associated with the trumpet worm in a community include the white furrow shell (Abra alba), the transparent razor shell (Phaxas pellucidus), the bivalve Mysella bidentata, the serpent star (Ophiura ophiura) and various polychaete worms.

It has been found in studies of Liverpool Bay that in areas where the sediment has been disturbed by dredging and more deposition has occurred, Lagis koreni and Phaxas pellucidus often come to dominate the community.

The trumpet worm inside and outside its tube.