What Is a Sea-Monkey?

Brine shrimp are crustaceans in the genus Artemia. Von Braunhut hybridized different species of Artemia to develop the artificial breed Artemia NYOS, or New York Ocean Science. Artemia NYOS, called Sea-Monkeys, grows larger and lives longer than regular brine shrimp. Kits still sell today, in 2012 for $5.95 to $25.95.

When they are born, Sea-Monkeys have one eye. They undergo molting up to seven times throughout their life cycle. Adults have three eyes, 11 pairs of legs and a tail. Sea-Monkeys breathe through their feet. Males have two reproductive organs and two large antennae, while females have a large egg sack on their abdomens and one small antenna. Males are slightly smaller than females. Sea-Monkeys mate when they are between 4 and 6 weeks old. Some have two-year life spans.

Sea-Monkeys reproduce sexually and asexually. Males attach themselves to a female and remain connected for a span of days to weeks. The female develops an egg sack in her abdomen at the base of her tail once the male detaches. The gestation period varies among females, suggesting that females are able to wait for favorable conditions before giving birth. Females can also produce offspring by themselves if no males are present. When females fertilize their own eggs it is called “parthenogenesis.” Litters yield about 20 Sea-Monkeys. As long as water is aerated every day and temperatures are kept at 82 degrees Fahrenheit, offspring reach sexual maturity after 12 days.

When you get a Sea-Monkey kit, you get several packets containing various items, including salt and dry brine shrimp eggs, yeast and spirulina. The brine shrimp undergo a process called "cryptobiosis," which is a state of suspended animation that allows the Sea-Monkeys to come to life when you add water.