The most dangerous jellyfish in the world

Portuguese caravel

Throughout the world there are different types of jellyfish, some more dangerous than others. To most dangerous jellyfish in the world It is known as the Portuguese caravel. Its scientific name is Physalia physalis and it has characteristics that make it unique.

In this article we are going to tell you everything you need to know about the most dangerous jellyfish in the world, its characteristics, danger and biology.

The most dangerous jellyfish in the world

most dangerous jellyfish in the world

Although often confused, the Portuguese man-of-war (Physalia physalis) is not a jellyfish. Its classification tells us that it is a polyp (hydra, aquatic serpent from Greece, and zoo, animal). It is a species of the Cnidaria phylum, which are aquatic, mainly marine, and have many years of history.

Physalia physalis It is a rare species, very unknown and uncommon on the beaches. However, are the Portuguese caravels dangerous for people? It is one of the most dangerous species in existence because the venom it stores in its stinging cells is so powerful that it can be fatal to children and even adults due to anaphylactic shock. The Portuguese man-of-war remind us of jellyfish, both for their appearance and for their sting.

Key features

This pseudomedusa is part of a gelatinous plankton formed by a group of related organisms in a colony, with different functional divisions to facilitate the survival of the entire colony. These are some of the main characteristics of the Portuguese caravel:

  • Regarding the morphology of this association of colonies, parts of its body are permanently floating in the water, especially the purple, pink, or blue bladder, which is full of gas. In this part there are also small holes that allow the oxygen uptake to be distributed throughout the colony through the network of pipes. This configuration allows it to be transported by ocean currents and winds, while the rest of the body remains underwater.
  • In addition, this division of its body gave it an appearance similar to a sailboat, hence its name: Portuguese caravel or Portuguese frigate.
  • In addition to this, has fingers or tentacles that can reach 50 meters or more, which can be used both to protect themselves from predators and to capture prey.
  • As a colony association, they are not animals with brains.
  • Physalia physalis it has a digestive system made up of several polyps called celiacs, and inside it they have an alimentary polyp, which is the founder of the colony.
  • Around the polyp there is a genital crown responsible for producing new cells called gametes. The resulting gamete colonies descend to the seafloor, where they attach and continue to release these sex cells. Once fertilization occurs, a polyp develops and rises to the surface through lipid accumulation.
  • As for its presence, the species has been found in certain areas of Spain, such as the Canary Islands, especially during the months of January and February, and may occasionally appear in March. However, the species usually lives in colonies in tropical and subtropical waters in regions such as the Atlantic coast, the Florida Keys, the Gulf of Mexico, the Caribbean or the Indian Ocean.

Sting of the most dangerous jellyfish in the world

sting of the Portuguese man-of-war

As we have mentioned, the Portuguese man-of-war present a danger because their filamentous stinging cells produce a poison that not only causes neurotoxicity, cytotoxicity and cardiotoxicity to prey, but also humans or other animals affected by encounters. They can kill us if it bites us. This bite occurs as a fully automatic defense mechanism when the Portuguese see a threat.

As for the stinging symptoms of the Portuguese man-of-war, there is a very wide range of severity. Mild symptoms, such as burning and itching in the area where the tingling occurs, they can even cause severe allergic reactions that can lead to anaphylactic shock and death. The most serious symptoms are severe pain, persistent nausea, vomiting, fever, and even death.

If you have never experienced the sting of the most dangerous jellyfish in the world, the following actions are recommended:

  • First, Get out of the water immediately.
  • Then I know you should wash the wound caused by the sting with sea water, vinegar or alcohol, without rubbing, to be very careful to remove any tentacle residue that may remain on the skin.
  • Never use fresh water to treat a sting as it has negative effects that can exacerbate the effects. Also, if possible, it is better to use hot water instead of cold water.
  • Lastly, You must go to the emergency room or the doctor to check the injury and its effects. Cortisone cream is usually recommended.

Distribution, habitat and curiosities

the most dangerous jellyfish in the world

It is uncommon to observe the presence of these jellyfish in temperate and cold climates. They are typically found in tropical and subtropical regions of the Pacific, Indian, and parts of the Atlantic Ocean. These polyps are less common in the Mediterranean, although they can be seen off the coast of Spain, where there are few predators. The aggregates of these organisms reach about a thousand specimens, and there is a strong dependence between them to ensure survival.

Despite its virulence, the Portuguese man-of-war has a variety of predators, among which we can mention manta rays, sea turtles, Glaucus atlanticus slugs and sunfish (also considered the heaviest fish in the world, with an average weight of 1000kg). In the presence of these creatures, the caravel is able to deflate its special bag, allowing itself to sink to the bottom of the ocean, giving the impression of being dead.

Likewise, There are other creatures that can coexist in perfect harmony with the poison of this jellyfish. Close to its tentacles we can find the clown fish, which is immune thanks to the mucous membranes that surround its skin, or the Nomeus gronovii, whose close association with man-of-war has earned it the title of Portuguese man-of-war fish. Any of these creatures are protected from predators by the tentacles of the caravels, which in turn allow them to attract other fish that make up their diet.

I hope that with this information you can learn more about the most dangerous jellyfish in the world and its characteristics.

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