I'm guessing much, much smaller than that, taking microsnails into account. https://www.atlasobscura.com/articles/found-the-worlds-tiniest-snail https://www.at

I'm guessing much, much smaller than that, taking microsnails into account. https://www.atlasobscura.com/articles/found-the-worlds-tiniest-snail https://www.atlasobscura.com/articles/found-the-worlds-tinie... But let me just add up their lengths, along with the lengths of all giant african land snails and all other snails, and divide by the total number of snails in the world ... is there a statistical trick that could answer this, like the one for counting undiscovered species? Probably not.