Among terrestrial species, that title would go to one of several closely related species of giant African land snail. According to Guinness World Records, the record holder, with a shell measured in 1978 at 27.3cm long, was named Gee Geronimo and kept as a pet in West Sussex.
Some marine snails can grow bigger than that, though. Australian trumpet shells can reach 72.2cm in length and weigh as much as an average three-year-old human. Some fossil ammonites exceeded 2m in diameter but, being more closely related to octopuses and squid, they don’t really count as snails.
Main image: close up on a snail shell/Getty
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