The Granrojo or big red (Tiburonia granrojo), is a newly discovered jellyfish that is apart of the Ulmaridae family, it is the only member of its genus so far that has been identified. The Granrojo is one of the largest sea jellyfish and is uncommon in various ways.

The Granrojo has been found all across the Pacific Ocean in Monterey Bay, Japan, Hawaii, and the Sea of Cortez. It lives in the ocean depths of 1,968 feet to 4,921 feet. The Granrojo can measure up to 2 to 3 feet in diameter. Instead of tentacles like most jellyfish, the Granrojo has thick, fleshy, oral arms. The jellyfish’s color is deep red.

Only twenty-three members of this species have been found to date. There has been only one small specimen (under 15 centimeters) that has been reclaimed for further study. The discovery of the Granrojo was announced in Marine Biology in 2003 by George Matsumoto and colleagues. There have also been several high resolution videos of the Granrojo taken by remote controlled submarines.