Neverita didyma, common name the bladder moon snail or moon shell, is a species of predatory sea snail, a marine gastropod mollusc in the family Naticidae, the moon snails.

[1] The size of an adult shell of this species varies between 20 mm and 90 mm.

Like all naticids, this species is a carnivore and a predator.

This marine species is found in the Yellow Sea or off the coast of the Madagascar, Mozambique and South Africa of the Indian Ocean.

In Korean cuisine the snails are used in a dish called golbaengi-muchim (moon snail salad).