Giant Tun – Tonna galea

The Giant Tun, also known as Tun Shell, is a species in the family of the Tonnidae and thus belongs to the class of the Gastropoda.

Giant Tun Shell - Tonna galea Martin Gastropoda diving canary islands atlantic ocean canaries species
Giant Tun – Tonna galea
Copyright: Martin Majewski


Tonna galea has a round, brown housing with lighter stripes. The body is black with white marbling. It reaches a maximum size of 35cm.

Habitat and Distribution

The Giant Tun lives on muddy, sandy or limestone ground down to a depth of 80m. When diving in the Canaries you can only rarely observe it. Its distribution area also covers the Mediterranean Sea, the Caribbean Sea, the Gulf of Mexico, the Atlantic Ocean, the Indian Ocean and the Western Central Pacific.


Tonna galea feeds mainly on sea cucumbers but also on other echinoderms.
It stuns its prey with asparagine and sulphuric acid. This dissolves the limestone skeleton of the prey.

Related Posts