Tiger Cowrie Question

Question:

Does any one know why the cowrie gets those green things on its shell and what purpose they serve? They look like small trees. Some times they cover the whole shell and sometimes only a part of the shell. I tried looking it up on the web, but didn’t find an answer.

Regards,
Judith

Answer - from Joe,

A quick answer to your query about the strange appendages on the Tiger Cowrie: what you see are the papillae on the mantle. They are thought to provide camouflage and to assist in respiration. The color of the mantle sometimes matches the sponge it feeds upon altho it never gets bright red like the sponge our tiger eats. The mantle is responsible for the cowrie shells being so beautiful, since it secrets building material from the outside, maintaining a colorful smooth high-gloss finish. (Most other shell-building species build their shells from the inside-out – which gives them nice glossy interiors, but duller exteriors.) The mantle covers the whole shells sliding up from both sides - it is retracted when you handle the animal. I have added two attachments, which show the mantle partially open.

Look for the two Humpback Cowries, they are very dark and hard to spot - but last time i checked they were in opposite corners of the tank covered by collector urchins and sea cucumbers.


Joe