Holothurians: Sea Cucumbers
Unlike their relatives, sea cucumbers are elongated in shape (like a sausage) and have a mouth with a crown of tentacles at one end, rather than in the middle like sea stars and urchins. Although not obvious, sea cucumbers do have very small calcareous plates called ossicles embedded in their body wall. These ossicles display various shapes and help taxonomists distinguish between different species.
Most sea cucumbers feed with their bushy tentacles which they either sweep over the seabed or hold into the water column. Small food particles get trapped on the sticky tentacles and are then forwarded to the mouth.
Holothurians have been found in dense patches on some Arctic shelves such as the Chukchi Sea . It remains unknown as yet whether they are dominating the invertebrate Arctic deep-sea epibenthos as they are in some other deep-sea areas of the world.
Close to 30 species of holothurians are known to occur in the Arctic
Page Author: Bodil Bluhm
Created: Oct 24, 2008
