Description

Also known as Giant Tun Shell, Helmet Tun, Oily Tun, Tun Shell.

Found nocturnally, over mud and sandy bottoms of coral and rocky reefs.
They feed on sea cucumbers.
Length - 23cm
Depth - 5-150m
Widespread Atlantic Ocean, Mediterranean, Pacific Ocean

These are a small family, their large shells have a distinct spiral.
They feed on sea cucumbers by sucking the food in with their large proboscis.
These large animals are able to burrow themselves completely in sand to escape predators. Ref: https://www.sealifebase.ca/summary/Tonna-olearium.html