Description of Dentalium ( Elephant’s Tooth Shell)
Systematic position of Dentalium
Phylum : Mollusca.
Genus : Dentalium
Habit and habitat:
Dentalium is marine. In shallow waters to depth they are found. Living partly buried obliquely in the mud and sand. The pointed foot protrudes from the larger ventral end of the shell for use in burrowing.
- Common name is Elephant’s tooth shell.
- Its body is slender dorsoventrally surrounded by the mantle which is elongate conical shell
- Open at both ends and slightly curved and tapered, so its like elephant tusk.
- In the mouth delicate ciliated and contractile tentacles with expanded tips, these are used as prehensile, serving to capture the protistans.
- The head has been reduced to little more than a mouth.
- Cilia on the mantle cavity create a current of water into it then collect the food.
- Ctenidia are absent and the large mantle cavity serves for respiration.
- The circulatory system consists only of blood sinuses, without blood and vessels.
- It is dioecioous.