[3][4][5] The Monterey Bay Aquarium Research Institute's remotely operated underwater vehicles have only sighted the jelly 27 times in 27 years.

A study conducted by the Journal of the Marine Biological Association of the United Kingdom, focusing on four Stygiomedusa gigantea present in the Gulf of Mexico, revealed information regarding the wider distribution of this species.

Furthermore, their bodies being made of either spongy tissue or jelly allows for the species to withstand the enormous deep ocean pressure of 40,000 kPa (5,800 pounds per square inch).

Daniel M. Moore, a marine biologist with Exeter University in the U.K. and chief scientist for Viking Cruises, states that the reason Antarctic waters below 160 feet haven't yet been well explored is that they are so difficult and expensive to reach.

However, the frequent encounters with this animal are from tourism expeditions in the Antarctic that are increasingly offering personal submersibles to guests to take photos.

This leads to the sighting of the giant phantom jellyfish hundreds of feet underwater off the coast of Antarctica's Rongé Island.

There have been observations of the rarely encountered Stygiomedusa gigantea at depths of 80–280 m (the mesopelagic and lower epipelagic zones) around the Antarctic Peninsula coastal waters.

The Norwegian Polar Institute and an international peer-reviewed journal called Polar Research, which corresponds with Daniel M. Moore of Viking Expeditions, found Stygiomedusa gigantea in the Antarctic Peninsula at Georges Point, Rongé Island, Fournier Bay, Anvers Island, and Paradise Harbour.

Daniel M. Moore noted that one potential explanation is that the jellyfish swim higher up to expose themselves to ultraviolet radiation, which will rid them of parasites.

Known to be one of the largest invertebrate predators in the deep sea, the giant phantom jellyfish's typical prey consists of plankton and small fish.

Scientists have observed that the large umbrella-shaped bell of S. gigantea provides food and shelter for T. pelagica, while the fish aids the giant phantom jelly by removing parasites.

It was inferred that T. pelagica is able to find its way back to the giant phantom jelly due to neuromasts that increase the sensitivity of low-frequency water movements—which the bell of the jellyfish emits.

[7] Despite having discovered only 118 individuals within 110 years (1899–2009), gelatinous mucus from the medusa have been found covering vents, indicating they may travel in swarms.

The S. gigantea has four brood chambers that protrude into the stomach in folded narrow ridges and epithelium that covers the gastric side.

[10] Above this band, there is a germinal line that forms a shallow groove with different epithelial cells that are more cubical in shape with large, rounded nuclei.