#1 Lion’s Mane Jellyfish (120 Feet)

While the blue whale is regarded as the largest marine animal, the lion’s mane jellyfish tops the list for length. These elegant and graceful creatures have tentacles that may extend as far as 120 feet, which makes them true underwater marvels. 

But scientists continue to be baffled by the function of these unusual limbs. According to some theories, the jellyfish may struggle with their large tentacles, leaving them more exposed to marine debris and predators.

Some claim that the long tentacles are effective predator traps that contain poison that keeps animals immobile. Whatever the cause of their unusual length, lion’s mane jellyfish continue to rank among the ocean’s most alluring and enigmatic animals.