The deep sea is largely unexplored and marine scientists are constantly surprised by the creatures they find roaming the depths in darkness. While exploring the Ningaloo Canyons off the coast of Western Australia with the SuBastian underwater robot, a team of researchers spotted what they believe is the longest organism ever recorded: a giant siphonophore of the genus Apolemia, Newsweek reports. The siphonophore, which is related to jellyfish and corals, looks like a long gelatinous string. It is formed by thousands of small, specialized cells—called zooids—that work together to create a functional colony. Researchers estimate the colony seen in the video above is more than 120 meters long. The scientists observed up to 30 new species and also spotted a bioluminescent octopus squid, a long-tailed sea cucumber, and several species of mollusks, barnacles, and squat lobsters. Their discoveries will add to the existing knowledge of the deep ocean, they say, and the management of protected areas.