A diver has captured footage of an unusual-looking jellyfish off the coast of Papua New Guinea, sparking interest among researchers. The video was captured by Dorian Borcherds, who owns Scuba Ventures in Kavieng, in the New Ireland province of PNG. Borcherds, who has been diving in the area for more than two decades, said he saw about three or four of the jellyfish and was struck by their intricate detail and the way they seemed to move decisively through the water. “They don’t have brains, so I don’t know how they do that,” he said. Looking for answers, he sent the footage to his wife in South Africa, who uploaded it to the Jellyfish app, a project Dr Lisa-ann Gershwin, a jellyfish expert at Australian Marine Stinger Advisory Services, co-founded. In her words, the app’s purpose is to “answer the age-old question: what is that blob and should I pee on [its sting]?” “As soon as I saw this one, honestly, I could barely contain my excitement,” she said. “I almost fell out of my chair.” Gershwin initially thought the footage was the second sighting of a mysterious jellyfish – Chirodectes maculatus – found decades ago on the Great Barrier Reef, but she now believes the “magnificent” creature is a new species. While Gershwin is confident in her findings, her paper on the species classification is yet to undergo peer review. Prof Kylie Pitt, a marine ecologist who specialises in jellyfish from Griffith University, said it could be a new species, but doesn’t think it would be possible to know for sure based only on a video. She said she had certainly never seen it before, but said a researcher would “need to hold the animal in your hand” to be sure of its species. “It would be great if we got the specimen and could describe its morphology, coupled with genetic testing,” she said. Prof Jamie Seymour, a toxicologist from James Cook University who specialises in Australia’s venomous animals, says he prefers Gershwin’s earlier theory, believing the jellyfish is a Chirodectes maculatus. Sign up to receive an email with the top stories from Guardian Australia every morning Gershwin had helped reclassify Chirodectes maculatus – a jellyfish that has been sighted only once off the coast of far north Queensland, after a cyclone in 1997. She said it had remained a mystery where the invertebrate had come from ever since. At first glance, she thought the new video could provide the answer. She enlisted the help of Peter Davie, a now retired – but still active – curator from the Queensland museum, where the original jellyfish specimen was kept. The pair pored over the footage from PNG frame by frame, and noticed the jellyfish had different markings, it was much larger – about the size of a soccer ball compared with something that could fit in your hand – and various other technical differences. To their delight, they decided this was probably a new species of jellyfish, probably belonging to the same genus as the one seen in 1997.