Which sea snail is the largest living gastropod?

The Australian trumpet is the largest living gastropod, with a shell that can exceed 70 centimetres in length.

Its scientific name is Syrinx aruanus, and it lives in shallow waters around northern Australia and nearby parts of the Indo-Pacific. The shell is long, heavy, and spindle-shaped, with a broad body whorl and a narrow pointed spire. Its size makes it one of the most conspicuous shells found in the region.

Despite its common name, the Australian trumpet is not a musical instrument or a trumpet-shaped coral. It is a predatory sea snail. The animal uses a proboscis and a specialized rasping radula to feed, and it can prey on other marine animals, including worms.

The species is sometimes confused with the queen conch, a famous large gastropod from the Caribbean. Queen conchs are substantial, but the Australian trumpet is longer and is generally recognized as the largest living gastropod by shell length.