An enormous jellyfish that washed up on the shores of Tasmania is a new species and possibly the largest ever found in Australia, and marine biologists at Australia's national science agency CSIRO are at work on classifying the new medusa. 

The mysterious jellyfish measures 5 feet (1.5 meters) across and was spotted by a family walking along the beach at Howden, south of the Tasmanian capital Hobart, in January.

Lisa-ann Gershwin, a CSIRO scientist, told the Australian Broadcasting Corporation that the species has been seen before, but it is unclassified and technically new to science.

"It's a whopper," Gershwin told ABC. "We do get large jellyfish and this one just happened to be this absolutely enormous specimen."

"I do hear from time to time people tell me 'we found this one that was really big', but this one really is, really big," said Gershwin, who has studied jellyfish for the past 20 years.

Gershwin said that the massive jellyfish is probably the largest ever found in Tasmania and that it could rival the size of jellies found in other parts of Australia.

"As Australian jellyfish go this would have to take the cake," Gershwin said in an interview with the Australian Associated Press.

While the giant jellyfish has yet to be officially classified, it is believed to belong to the Cyanea group. Some Cyanea jellyfish, such as the Lion's Mane, are among the world's largest species and can grow about 10 feet (3 meters) across.

Speaking with the BBC, Gershwin described the washed-up jellyfish as looking "like a dinner plate with a mop hanging underneath."

"They have a really raggedy look to them," she said.

This unclassified species has been known to Gershwin for some time. It is among three new Cyanea species that Gershwin and her colleagues are working to classify, the BBC reported.