A new species of jellyfish has been discovered in the Gulf of Venice—but where it hails from remains a mystery. In a phenomenon known as a bloom, the now-named Pelagia benovici showed up in such force in September that it interfered with fishing; citizen jellyfish trackers who were unable to identify it as a local variety contacted scientists, the Guardian reports. Italian researchers who studied the "beautiful yellow-ochre" jellyfish (stunning image here) speculate in the journal Zootaxa that the species came to the North Adriatic Sea in a ship’s ballast water (carried in tanks to help the ship maintain stability) from its native habitat, where it has yet to be recorded.
That sea is "one of the most investigated [marine] areas of the world," writes Stefano Piraino, one of the zoologists involved in the study, in the Conversation, meaning there's no way the jellyfish hails from there and somehow went unnoticed. And as of March, the creature has vanished from the Venice lagoon, but they can "suddenly come back," Piraino writes. Among the other details scientists shared: Pelagia benovici joins what is currently "the only valid species" in the genus Pelagia, a mauve variety that obliterated a $2 million salmon farm in Northern Ireland in a "spectacular attack," the AP reported in 2007. (Jellyfish can cause a great deal of mischief: They are such a nuisance in South Korea that a robot has been designed to destroy them.)