Violet Sea Urchin – Sphaerechinus granularis
The Violet Sea Urchin, also known as Purple Sea Urchin, is a species in the class of Sea Urchins and thus belongs to the Phylum of the Echinodermata. Sphaerechinus granularis was first described in 1816 by Lamarck.
Even if its common name is Violet Sea Urchin, it does not mean that it is always violet. It can be white, pink, brown or reddish. Sometimes Sphaerechinus granularis also has a certain colour and only the tips of its spines are white. Compared to other sea urchins, its spines are rather blunt.
Between its spines theViolet Sea Urchin has tube feet with suction cups. It can hold algae, shells and other materials to protect and camouflage.
Sphaerechinus granularis is up to 15cm in diameter and its spines reach a length of up to 2cm.
Habitat and Distribution
The Violet Sea Urchin lives on stony or rocky ground and in sea grass meadows. It is found in depths of 2 to 100m. In calm water, Sphaerechinus granularis is generally somewhat shallower, whereas in moving waters it is rather a bit deeper.
When diving in the Canaries you can observe it frequently.
In addition, its distribution area extends from the North Sea, across the Channel Islands and Ireland, along the European and African coast to the Gulf of Guinea. The Violet Sea Urchin is also found in the Mediterranean Sea, around the Azores, Cape Verde and Madeira.
Sphaerechinus granularis feeds on detritus, algae, sea grass roots, mussels and snails.
In order to be protected against predators, it camouflages itself by masking. For this purpose, the Violet Sea Urchin holds various materials, such as snail shells, mussels or algae, with the suction cups of his tube feet.
The Violet Sea Urchin can be reproduce all year round. However, the reproduction reaches its peak in spring to early summer. Sperm and eggs are released into the open water, where the eggs are then fertilized. The embryos develop into plankton larvae, which sink to the ground after several months. After a metamorphosis, they become young Violet Sea Urchins.