The oceans are home to countless animal species, including the fascinating and magnificent cnidarians. It includes the class of Scyphozoa, which corresponds to one of the strangest types of jellyfish that exists and which generally poses no danger to humans. In this PlanetAnimal fact sheet, we are going to tell you about a member of the class Scyphozoa, commonly called, because of its particular appearance, the fried egg jellyfish or the jellyfish Cotylorhiza tuberculata.Read on to learn more about this magnificent animal!
Origin
- Europe
- Albania
- Croatia
- Spain
- France
- Greece
- Italy
Features of Fried Egg Jellyfish
The scientific name for the fried egg jellyfish is Cotylorhiza tuberculata. It is a small-medium sized animal that measures between 20 and 40 cm, but its umbrella can measure up to 25 cm in diameter. This last structure is quite peculiar to this animal, because, seen from above, it looks like a fried egg. It is round in shape, cream in color with a domed center and a brownish or reddish coloration.
It has sensory organs and eight oral arms, from which several branches branch out to form tentacles.It is lined with knob-shaped protrusions of different colors, such as purple, white or blue, which makes it even more distinctive from its congeners. Beneath these structures, the coloration can vary from greenish to brownish or orange, depending on the algae that live there in association.
Its body is mostly gelatinous and its tentacles are loaded with a poisonous substance that is not dangerous to humans. On contact, it causes only mild to moderate irritation, depending on the person's sensitivity. A remarkable characteristic of this cnidarian is its sexual dimorphism: the females have filaments where they will house the embryos during their development after fertilization.
Habitat of the fried egg jellyfish
The habitat of the fried egg jellyfish is in the waters of the Mediterranean Sea, so it lives near the coasts of countries such as Spain, France, Italy or Greece, among others.Depending on the time of year, it is found near the coast or in open sea areas. In addition, during one of its reproductive phases, it moves to shallow waters with a rocky bottom. This jellyfish has also been observed in the Minor Sea, the Aegean Sea and the Adriatic. Large quantities tend to accumulate in closed sea areas used for tourist activities, causing some inconvenience to people.
Habits of the Fried Egg Jellyfish
This is a jellyfish that mainly inhabits shallow waters, but also moves at certain depths. Although it can be carried by water currents, it is capable of swimming on its own, moving both vertically, which it does by contracting and extending its body, and horizontally, by moving immersing deeply.
If there is a lot of movement in the surface water, it tends to submerge and settle in calmer areas.It is common for large aggregations of individuals to form along the shoreline in late summer and fall, coinciding with the peak beach season. When the water begins to cool with the onset of winter, the fried egg jellyfish move to the offshore waters. On the other hand, it is commonly surrounded by certain species of fish, unaffected by its toxicity, which take refuge in its arms to escape its predators.
Fried Egg Jellyfish Feeding
The fried egg jellyfish has two ways of feeding or types of feeding. One of them is to catch small fish, and even smaller jellyfish, which she inoculates with venom using her nematocysts. This substance paralyzes the prey, allowing the jellyfish to devour it slowly. It also feeds on marine plankton.
The other mode of feeding of the Mediterranean jellyfish is the symbiotic relationship it establishes with certain algae, in particular the photosynthetic dinoflagellates.The jellyfish provides a place where these single-celled forms can live. In return, they store, through their photosynthetic action, energy after fixing macromolecules that are used by jellyfish, thus obtaining an important source of nutrition that influences their development.
Reproduction of the fried egg jellyfish
The reproduction of the fried egg jellyfish is similar to that of other cnidarians, with a sexual phase and an asexual phase. The sexual phase is divided into four stages, which occur in an annual cycle. Population growth is strongest in summer. Sexually differentiated jellyfish mature in summer and adult females are internally fertilized by sperm released by the male in a process that tends to occur between August and October. Then the planula develop and, once the gestation is over, a large number of them are released into the water, where they move towards the rocky bottoms to settle and spend a sessile life time.
The planula attaches itself to the substrate to give rise to the polyp and it is at this stage that the symbiosis with the algae begins which will last its entire life. This is where the asexual reproduction phase comes in, in fact, the polyp forms others identical to itself to end up metamorphosing and giving rise to the ephyria, which will be released between spring and summer. Then they turn into free jellyfish.
Preservation status of the fried egg jellyfish
The Fried Egg Jellyfish is not considered to be at risk of declining population levels. Indeed, it is not on the red list of the International Union for the Conservation of Nature. On the contrary, this animal experienced high growth rates during the summer season.
This has led to the use of fishing nets in an attempt to contain their passage and avoid contact with bathers in tourist areas.The growth was such that in just one year up to five tons of this jellyfish were collected. Although, as we mentioned, this jellyfish does not possess a deadly poison for people, but it can still cause some discomfort to sensitive people.
Photos of Fried Egg Jellyfish or Cotylorhiza tuberculata
