About Strongylocentrotus fragilis Jackson, 1912
This species, Strongylocentrotus fragilis Jackson, 1912, is a regular sea urchin. It has a spherical test, with the anus positioned on the top and the mouth on the bottom. Individual tests are somewhat flattened, and the species has a pale pinkish base color with white spines. It is a deep-sea abyssal species that can occur in large numbers where food is abundant. It lives along the western coasts of North America at depths of hundreds of meters, distributed across the continental shelf and slope, and is most abundant in the 200 to 300 meter depth range.
