Turritopsis dohrnii

How long does the immortal jellyfish live? Potentially forever. Which gets more impressive considering these creatures have been floating through the oceans long before the dinosaurs went extinct (66 million years ago) – it's biologically possible for a single immortal jellyfish to have been alive for this entire time. At this time, the immortal jellyfish is not considered extinct or endangered. This is because these jellyfish are immortal and have survived millions of years. In fact, they've been around since before the dinosaurs. With that in mind, they're likely to remain long after humans, too. Like a typical jellyfish, the “immortal” T. dohrnii begins its life as a free-floating larva. It finds a hard surface to attach to, such as a rock or shell, and matures into a branching, plant-like polyp. From there, multiple young jellyfish bud off from the polyp and turn into medusae, or adults.

Scientific name: Turritopsis dohrnii

Higher classification: Turritopsis

Rank: Species

Shape: bell-shaped

Family: Oceaniidae

Kingdom: Animalia

Order: Anthoathecata

                                      This species of jellyfish will transform back into a hydroid colony, meaning this jellyfish will be reborn at death.