Lighthouse jellyfish are immortal.

The lighthouse jellyfish has the ability to return to its hydroid-type state after sexual maturity and can repeat this process indefinitely. Lives mostly in tropical waters. It is carnivorous, feeding on plankton, small crustaceans, polychaetes and even small fish. Lighthouse jellyfish can reproduce asexually from hydroids and are the only known organisms capable of reverting from the sexually mature stage to the larval stage.

It takes 25 to 30 days to reach the sexually mature stage in water temperatures of 20 degrees Celsius. They are mainly found in Caribbean waters, but ballast water discharged by ocean-going ships has gradually spread them to other neighboring seas, off Spain, Italy and Japan.

Expanded Information

The lighthouse jellyfish (Turritopsis nutricula), named by McCrady in 1857, is only one member of the genus Lighthouse Jellyfish, which includes nine other species. The lighthouse jellyfish and the short-stalked lighthouse jellyfish have been documented in China.

Jellyfish in the general sense refers to the jellyfish-type stage of cnidarians, and according to this definition, jellyfish in the general sense includes most species of Hydrozoa and all species of Mantle Jellyfish, of which there are more than 3,000 known species. The jellyfish stage is only one part of the life history of cnidarians, so the proportion of the total life history time spent in the jellyfish stage varies greatly from species to species.

Baidu Encyclopedia - Lighthouse Jellyfish