Spatangus raschi

This burrowing sea urchin belongs to the family Spatangidae, a group of heart urchins adapted for life beneath the seafloor. Its body is oval and covered in dense spines that assist with burrowing into soft sediments, where it moves slowly while ingesting organic material and fine particles. As a deposit feeder, it plays a role in bioturbation, reworking sediment layers and cycling nutrients within benthic marine ecosystems, which can influence the composition and health of surrounding seafloor communities.

Spatangus raschi is found in cold and temperate marine waters across the North Atlantic and adjacent regions, with recorded populations off Norway, Sweden, the United Kingdom, Ireland, Spain, Italy, Morocco, Svalbard and Jan Mayen, the Faroe Islands, Canada, and Australia. It inhabits soft sediment seabeds, typically at depths where it can burrow undisturbed.

The species is classified as Critically Endangered, with ongoing threats including bottom trawling and other fishing gear that physically damages seafloor habitats and disturbs burrowing urchins directly. Additional pressures include ocean warming and acidification, both linked to climate change, sediment disturbance from human coastal and offshore activities, and pollution from marine debris. Population trends are currently unknown, limiting precise assessment of decline rates.

Specific conservation programs targeting this species are not well documented, though broader marine protected area designations and fishing gear regulations in parts of its range may offer some incidental habitat protection. Continued bottom trawling in areas of its distribution remains a significant concern.

Given the combination of habitat degradation, climate-related ocean stressors, and limited population data, the species' conservation outlook remains uncertain, with its Critically Endangered status reflecting significant cause for concern.

Deep-water sandy and muddy seafloor sediments in the North Atlantic, typically found at depths between 50-200 meters where it burrows in soft substrates. The species requires stable sediment environments with specific grain sizes and organic content for feeding and reproduction.