According to the USGS, an adult female normally lives about three months. Aquarium hobbyists report lifespans of more than six months. Sea monkeys are actually brine shrimp of the genus Artemia.
While the adult brine shrimp's life is relatively short, its eggs can survive for years in a dormant cyst form. Viable eggs hatch within 48 hours after being placed in water at the proper level of salinity. Entrepreneur Harold von Braunhut used this property of brine shrimp eggs in marketing "Sea Monkey" kits containing salt, brine shrimp eggs, borax, soda, yeast and food for the newly hatched brine shrimp.