Belonging to the Holothurioidea.

One of the Holothurioidea.

Holothurian - Any cylindrical echinozoan, usually free-living, belonging to the class Holothuroidea, and characterized by the absence of an articulated test (external shell or other hard covering) and by the reduction of skeletal parts to microscopic sclerites; a sea cucumber.

echinoderm having a flexible sausage-shaped body, tentacles surrounding the mouth and tube feet; free-living mud feeders: sea cucumbers

A member of the class Holothuroidea.