The Granrojo jellyfish (Tiburonia granrojo) is a deep-sea jellyfish unlike any other. It’s a big, red jellyfish that doesn’t have the long, stinging tentacles we usually see on jellyfish.
It lives in the deep ocean, sometimes more than a mile down, in the cold, dark waters of the Pacific Ocean. It wasn’t discovered until 1998 by MBARI because it lives in such a remote environment. Hence there’s still a lot to learn about how it lives. Let’s find out what we do know about this unusual creature.
Appearance
The Granrojo jellyfish is huge, growing over three feet across (the size of a small car tire). Observations indicate that the bell diameter of this jellyfish can range from approximately 2.6 to 4.9 feet (0.8 to 1.5 meters) But what’s strange is that it doesn’t have the usual long, stinging tentacles of most jellyfish. Instead, it has these thick, fleshy arms, four to seven of them, that it uses to grab food.
Throughout the history of the species, only twenty-three members have ever been observed by humans. One of these was quite small, at only six inches.
Both its arms and its bell (the main body) are a deep red color, which is why it’s called “Granrojo,” meaning “big red” in Spanish. The texture of the bell and oral arms is likely smooth and gelatinous, typical of jellyfish.
Because it lives so deep in the ocean, scientists haven’t been able to study it much, but they think it’s probably like other jellyfish in some ways. It probably doesn’t have a heart, bones, eyes, or even a brain, and its body is mostly made of water.
Habitat
They are primarily found in deep-sea habitats, specifically in the northeastern Pacific Ocean. Its range includes areas off the coast of North America, Baja California, Hawaii, and Japan. But, because of the depths that they live at, around 600 to 1500 meters (2,000 to 4,800 feet), they are rarely seen and could live in other parts of the world’s oceans. Some scientists believe that these jellyfish can handle different temperatures of water.
One specimen of the species was obtained and placed in the National Science Museum in Tokyo, but, like most deep-dwelling species, it’s unlikely that easy capture and upkeep of these creatures is going to be possible.
Diet
It’s believed that these unusual jellyfish use their four-seven arms as a way to catch and consume prey. They are also considered to be avid hunters, moving easily after their prey. Their diet is likely similar to that of other jellyfish. They mostly likely eat small fish and zooplankton that they’re able to capture with their tentacles.
Some scientists have considered whether or not the ”big red” jellyfish can use their arms, as other jellyfish use their tentacles to entangle and sting their prey.
Reproduction
These jellyfish likely reproduce in the same way to other jellyfish. That is, through several different stages. They release Superman’s egg into the water which forms a planula. This planula hooks to the bottom of a rock or some other structure and grows into a polyp.
This stage lasts for several months or even years. Now, the polyp uses asexual reproduction, cloning itself into an ephyra. This grows into an adult jellyfish.
Scientists have assumed that these jellyfish live similarly short lives to other species of jellyfish. Generally, they live between two and six months.
Threats
Due to the fact that these jellyfish live deep within the ocean’s waters, they are subject to few threats. Human fishing practices are unlikely to reach this deep, nor are the immediate effects of pollution and coastal erosion. Climate change is always something to be concerned about, but the depth at which these creatures live affords them some protection.
Despite this, they are likely always at threat from other marine creatures that may choose the “big red” as a source of food.
5 More Facts About the Granrojo Jellyfish
- The Granrojo jellyfish lives up to 4,800 feet below the ocean’s surface.
- Little is known about their life and habits.
- The Granrojo jellyfish is one of the largest in Earth’s oceans.
- Scientists assume that the Granrojo jellyfish is similar in its diet and reproductive habits to other jellies.
- It seems to move relatively slowly and deliberately compared to other jellyfish, possibly using its oral arms for propulsion.
FAQs
How does the Granrojo jellyfish’s red coloration benefit it in the deep sea?
At the depths where the Granrojo lives, red light is absorbed by the water, making the jellyfish effectively invisible to many other deep-sea creatures. This camouflage can be advantageous both for hunting and avoiding predators.
Why doesn’t the Granrojo jellyfish have tentacles?
Scientists aren’t entirely sure why the Granrojo evolved without tentacles, but it’s speculated that its deep-sea environment, with different prey and fewer predators, may have favored the development of its unique oral arms for capturing food.
What is the role of the Granrojo jellyfish in the deep-sea ecosystem?
Its ecological role is still being investigated. As a potential predator of other jellyfish, it likely plays a part in regulating deep-sea jellyfish populations. Further research is needed to understand its full impact on the deep-sea food web.
Are there any known predators of the Granrojo jellyfish?
Due to its size and deep-sea habitat, the Granrojo likely has few natural predators. However, larger deep-sea creatures, such as certain fish or squid, could potentially prey on them.
