Eupolymnia nesidensis

This marine polychaete worm belongs to the family Terebellidae, a group of tube-dwelling annelids known for their elaborate feeding tentacles. Eupolymnia nesidensis constructs a mucus-bound tube reinforced with sediment and shell fragments, from which it extends numerous long, retractable tentacles across the surrounding substrate to collect organic detritus and small particles. This deposit-feeding behaviour helps process sediment and cycle nutrients, contributing to the health of benthic marine communities.

As with many terebellids, the species is largely sedentary as an adult, remaining anchored within its tube for extended periods while continuing to forage through tentacle extension.

The species has been recorded across a wide but patchy range spanning coastal waters of Europe, the North Atlantic, the Mediterranean, and parts of North America and Australia, including the United Kingdom, Norway, Sweden, France, Ireland, Italy, Spain, Greece, Iceland, Canada, and the United States, among other locations. It inhabits shallow marine and coastal sediment environments.

Its Vulnerable status stems from ongoing coastal development and urbanization, which degrade and fragment seabed habitats, along with marine pollution and chemical contamination that affect sediment quality and water conditions. Tourism-related disturbance in coastal zones adds further pressure, and the species' reliance on specific localized habitats increases its vulnerability to these cumulative impacts.

No population figures are currently available, and the population trend is listed as unknown. Targeted conservation measures specific to this species have not been widely documented, though it may benefit indirectly from broader coastal habitat protections and marine pollution controls in some of the countries where it occurs. Given the continued pressures on coastal environments across its range, its long-term outlook remains uncertain without further monitoring data.

This marine polychaete worm inhabits shallow coastal waters and benthic sediments in the Mediterranean Sea. It typically occurs in sandy and muddy substrates in nearshore environments where it constructs characteristic tubes.