It is found on the seabed in the north east Atlantic Ocean and adjoining seas to a depth of 200 metres (660 ft).

[1] Amphiura filiformis lives submerged in soft substrate with part of its arms projecting above the surface of the sand for the purpose of suspension feeding and gas exchange.

[2] It has been calculated that they can travel about 10 kilometres (6.2 mi) in this time and this allows A. filiformis to expand its range, or recolonise areas where it has suffered mass deaths, as happened in a cold-related event in the German Bight in 1977.

It is suggested that this build up in numbers was mainly due to eutrophication of the North Sea, although overfishing of the flatfish that feed on the brittle stars may have played a minor role.

A study in the North Sea found that only 4% of adults had a full complement of arms and the rest had damaged, missing or regenerating limbs.

The researchers were interested in studying how the nervous system recovered during arm regeneration as this could have applications for understanding and treating neurodegenerative diseases in humans.