In this article we will discuss about the structure of Cucumaria with the help of a diagram.
1. It is commonly known as “sea cucumber”, is marine and is found in shallow waters.
2. Body elongated, cylindrical, five sided, swollen in the middle and narrow at two ends.
3. The mouth and anus (cloaca) are situated at opposite ends.
4. Body surface is traversed by five longitudinal ridges -the ambulacral ridges each of which is bordered by double rows of tube feets.
5. The spines, pedicillariae, branchiae or plates are all absent but small calcareous particles are found embedded in the body wall.
6. Mouth is surrounded with a small ring-like peristome and a collar-like introvert. The introvert bears long, highly branched and dedritic tentacles.
7. Madreporite is internal and so also the respiratory organs, which are in the form of 3 well developed respiratory tree.
8. Sexes are separate and development through auricularia larva.