How do desert snails survive long dry periods in the Sahara Desert?

To survive the extreme environmental stress of the Sahara Desert, desert snails utilize a process called aestivation, a form of dormancy that allows them to remain inactive for long periods—sometimes lasting several years—until rainfall revives them.12

During these dry periods, the snails retreat into their shells and secrete a protective membrane known as an epiphragm. This barrier, composed of mucus and lime, covers the shell opening and effectively resists desiccation by preventing the loss of internal moisture. This adaptation is essential for their survival in an arid climate where water availability is highly unpredictable.31