Wikipedia says so, so it must be true: “The Lions Mane Jellyfish is the largest jellyfish in the world. They have been swimming in arctic waters since before the dinosaurs (over 650 million years ago) and are among some of the oldest surviving species in the world. The largest can come in at about 6 meters and has tentacles over 50 meters long. Pretty amazing when you think these things have been swimming around for so long.”
Perhaps more frightening, is that the largest known jellyfish of this kind washed up on the Massachusetts Bay in 1870. Can you fucking imagine that? It was 7.5 ft in diameter.
Also? That’s the best goddamn name for a jellyfish ever.