Different types of Jellyfish

Jellyfish are a group of marine animals that have no backbone. They can be found in all oceans and seas around the world, but they are most common near coastal areas where there is plenty of food for them to eat. Jellyfish come in many shapes and sizes, from tiny ones less than an inch long to giant species more than 20 feet across.

The Most Common Types of Jellyfish

There are two main types of jellyfish: box jellies and sea nettles or Portuguese man-of-war stings. Box jellyfish look like large transparent boxes with tentacles sticking out of each side. Sea nettle stingers resemble small balloons filled with water. Both kinds of jellyfish contain venomous nematocysts which inject poison into their prey when touched by one of these creatures. The only way to avoid being stung by either type of jellyfish is not to touch it. If you do get stung, wash your skin immediately with soap and warm water. Do NOT rub the area because this will spread the poison further through your body. You should also seek medical attention if you feel ill after getting stung.

How Many Species of Jellyfish Are There?

It’s hard to say exactly how many different species of jellyfish exist on Earth today. Scientists estimate that there could be as many as 10 million different varieties of jellyfish worldwide! Some scientists believe that we may never know just how many species of jellyfish actually exist. It would take years of research to study every single kind of jellyfish known to science. 

Size And Characteristics

Most jellyfish are about 1/2 – 2 inches wide. However, some larger species can grow up to 30 feet across. A few very rare species can even reach 100 feet in diameter. Their bell shape makes them easy to spot at night since they glow under black light.

All jellyfish have eight arms surrounding a central mouth called a gastrovascular cavity. This cavity contains digestive enzymes used to break down food. Each arm has three rows of tentacle cells containing nematocyst capsules.

These capsules release their contents when triggered by contact with another animal. When a jellyfish touches its victim, the tentacles pierce the skin and inject the nematocysts directly into the bloodstream. Once inside the blood stream, the nematocysts dissolve and cause pain and inflammation.

In addition, the nematocyst capsule releases toxins that paralyze muscles so the jellyfish can feed off its meal without having to move away.  

Life Cycle Of Jellyfish

Most jellyfish reproduce using eggs instead of sperm. Eggs float freely until they hatch into larvae. Larvae drift along currents looking for places to settle. After settling, the larva attaches itself to a suitable surface such as coral reef rocks or seaweed.

As the larval stage continues, the creature grows bigger and eventually transforms into a polyp. Polyps live attached to surfaces underwater. They use sunlight to make energy and produce oxygen. At first, they remain stationary but later begin moving around slowly.

Eventually, they develop legs and become adults. Adult jellyfish swim near the ocean floor where they wait for passing fish to eat. Then, they attach themselves to the fish’s gills and suck nutrients from the fish’s blood.

Jellyfish Sting Facts: What To Know Before Stinging Them

The stingers found on most jellyfish are made out of two parts – an outer sheath which houses the venom sac and inner tube-like structure. These structures contain nematocysts, microscopic tubules filled with powerful chemicals that deliver painful stings.

The nematocysts are released only when touched by other animals. If you get stung by one of these creatures, it is important not to panic because your body will automatically try to neutralize the poison before any symptoms appear. In fact, if you do experience severe allergic reactions, this means that your immune system was able to successfully fight back against the toxin.

If you’re stung by a large number of jellyfish, however, you should seek medical attention immediately.

How to Avoid Being Stung By Jellyfish?

If you find yourself swimming through waters infested with jellyfish, here’s what you need to know about avoiding being attacked by them.

First, avoid areas where there are lots of jellyfish. The more jellyfish present, the greater chance you’ll encounter one. Also, be careful during low tide periods. During high tides, water levels rise quickly and may wash over exposed reefs. This makes it easier for jellyfish to hide in crevices and undersea ledges.

 Second, don’t go too deep. Most jellyfish prefer shallow depths. However, some species have been known to venture down deeper. So, keep an eye open for signs of life at those depths.

Third, wear protective clothing. Wearing long pants and shoes helps prevent cuts and abrasions. A wetsuit also protects swimmers from getting stung. Finally, remember that even though jellyfish look like floating balls of gelatinous material, they actually possess many tentacles.

Therefore, never approach a jellyfish directly. Instead, gently brush past it while keeping your distance.

What should I do if I am stung by a Jelly Fish?

In case you were stung by a jellyfish, follow these steps to help reduce swelling and pain.

1) Remove the tentacle. You can remove the entire tentacle using tweezers or pliers. Alternatively, you can cut off the end of the tentacle with scissors.

2) Apply ice packs to affected area. Ice reduces inflammation and speeds up recovery time.

3) Seek immediate medical care. Do not attempt to treat the wound yourself as doing so could cause infection.

4) Wash wounds thoroughly after treatment. Cleaning the wound well removes dead tissue and prevents bacteria from entering.

5) Keep away from saltwater until healed. Saltwater causes skin irritation and increases risk of infections.

6) Use sunscreen lotion daily. Sunscreen blocks harmful rays from reaching the skin. It also keeps sunburned skin cool and moist.

7) Take antihistamines. Antihistamine medications relieve itching caused by allergies. They also decrease swelling around the sting site.


Jellyfish are fascinating animals. Their ability to move across vast distances without leaving behind trails has fascinated scientists since ancient times. Although most people enjoy seeing jellyfish on their vacation trips, few realize how dangerous they really are. Fortunately, we now understand much better than ever before just how deadly jellyfish truly are. Hopefully, this article will serve as a reminder to all who visit our beautiful beaches that jellyfish pose a serious threat to human health.

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