Turritopsis dohrnii

Species of small, biologically immortal jellyfish

Turritopsis dohrnii, commonly known as the immortal jellyfish, is a species of small, biologically immortal Medusozoa (jellyfish) found worldwide in temperate to tropic waters. It is one of the few known cases of an animal capable of completely reverting to a sexually immature, sedentary polyps colonial stage after having reached sexual maturity as a solitary individual. Like most other hydrozoans, T. dohrnii begin their lives as tiny, free-swimming larvae known as planulae.

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