Telescopium telescopium

Telescopium telescopium, commonly known as the telescope snail, is a species of snail in the horn snail family Potamididae found in mangrove habitats in the Indo-Pacific. They are large snails that can grow up to 8 to 10 cm (3.1 to 3.9 in) in length and are easily recognizable by their cone-shaped shell.

Telescope snails are edible and are eaten in parts of Southeast Asia. They are known locally as bagongon or bagungon in the Philippines; and rodong or berongan in Malaysia, Singapore, and Indonesia.