Dr Lisa-ann Gershwin, of Australia's CSIRO government agency, said that scientists had known about the species for a while but had not yet classified it.
She described the specimen as a "truly magnificent animal".
This species was part of the Lion's Mane group, she said.
These jellyfish "look like a dinner plate with a mop hanging underneath - they have a really raggedy look to them", she said.
It was one of a "species I've known about for a while but it's not yet named and classified", she said. "We're very eager to know more about it."
Sure, maybe a "truly magnificent animal" in the water, but on a beach? "Puke puddle." Yeah, we already established that. Speaking of -- one time I came across a puddle of puke right outside the bar and you know what I did? "Notified a bouncer to clean it up?" Wrote my initials in it with a stick.