Sea urchin -Colobocentrotus- in glass
AN445
The helmet urchin, Colobocentrotus atratus, is one of the rare sea urchin not to have spikes, but to be perfectly adapted to strong waves. It is indeed solidly clinged with its suction cups -the podias- in the intertidal zone, where no bigger animal could hold. It is found around the Indian Ocean, and up to Polynesia. And its test - the shell- is just naturally purple.
