Jellyfish (Sycophozoa) are delicate, soft-bodied animals. They are invertebrates—jellyfish have no bones, exoskeleton, or shell to protect or support them. Instead, the water in which they live provides their body with the structural support it requires. If a jellyfish is removed from water or is washed ashore, it collapses and dies.Jellyfish are Cnidaria, a group of animals that also includes corals, hydras, and sea anemones. Cnidaria are all radially symmetrical. Their body parts are roughly symmetrical when viewed around a central axis. Jellyfish have no left or right side, when viewed side-on, they look approximately the same from every angle.
The infamous box jellyfish developed its frighteningly powerful venom to instantly stun or kill prey, like fish and shrimp, so their struggle to escape wouldn’t damage its delicate tentacles.
Their venom is considered to be among the most deadly in the world, containing toxins that attack the heart, nervous system, and skin cells. It is so overpoweringly painful, human victims have been known to go into shock and drown or die of heart failure before even reaching shore. Survivors can experience considerable pain for weeks and often have significant scarring where the tentacles made contact.
Jellyfish live in oceans throughout the world. Most jellyfish live in marine environments, a few species inhabit saltwater lakes. All species of jellyfish that are said to be freshwater dwelling are in fact Hydrozoans (not Scyphozoans). Some jellyfish prefer warm, tropical waters while other species tend to prefer cold, arctic or antarctic waters.
Box jellies, also called sea wasps and marine stingers, live primarily in coastal waters off Northern Australia and throughout the Indo-Pacific. They are pale blue and transparent in color and get their name from the cube-like shape of their bell. Up to 15 tentacles grow from each corner of the bell and can reach 10 feet (3 meters) in length. Each tentacle has about 5,000 stinging cells, which are triggered not by touch but by the presence of a chemical on the outer layer of its prey.
Box jellies are highly advanced among jellyfish. They have developed the ability to move rather than just drift, jetting at up to four knots through the water. They also have eyes grouped in clusters of six on the four sides of their bell. Each cluster includes a pair of eyes with a sophisticated lens, retina, iris and cornea, although without a central nervous system, scientists aren’t sure how they process what they see.
- Did you know?
- Sea turtles are unaffected by the sting of the box jellyfish and regularly eat them.
- 2.Cone Snail
- This little beautiful looking Cone snail can be as deadly as any other animal on this list. One drop of its venom is powerful enough to kill more than 20 humans. If you ever happen to be in warm salt water environment (where these snails are often found) and see it, don’t even think of picking it up. Of course, the true purpose of its venom is to catch its prey, and not to kill you.Symptoms of a cone snail sting can start immediately or can be delayed in onset for days. It results in intense pain, swelling, numbness and tingling. Severe cases involve muscle paralysis, vision changes and breathing failure. There is no antivenom. However, only about 30 human deaths have been recorded from cone snail envenomation. The cone snail uses a “harpoon” loaded with venom that it launches with a muscular contraction to inject its prey.
- 3.Blue Ringed Octopus
- The blue ringed octopus carries enough poison to kill 26 adult human beings within minutes. It has no antidote.Its painless bite may seem harmless, but the deadly neurotoxins begin working immediately resulting in muscular weakness, numbness, followed by a cessation and breathing and ultimately death.They can be found in tide pools in the Pacific Ocean, from Japan to Australia.The poison is not injected but is contained in the octopus’s saliva, which comes from two glands each as big as its brain. Poison from the one is used on its main prey, crabs, and is relatively harmless to humans. Poison from the other gland serves as defence against predators. The blue-ringed octopus either secretes the poison in the vicinity of its prey, waits until it is immobile and then devours it, or it jumps out and envelops the prey in its 8 tentacles and bites it.The blue-ringed octopuses are three octopus species that live in tide pools and coral reefs in the Pacific and Indian Oceans, from Japan to Australia.
4.Death Stalker Scorpion
The Deathstalker (Leiurus quinquestriatus), is a species of scorpion, a member of the Buthidae family. It is also known as an Omdurman scorpion, or Israeli desert scorpion. The name Leiurus quinquestriatus roughly translates to “five-striped smooth-tail”. Other species of the genus Leiurus are often referred to as “deathstalkers” as well.
The Deathstalker is straw yellow in color, and can grow 3.5 to 4.5 inches (9 to 11.5 cm) in length. It is of a slight build compared to other scorpions, with a long thin tail and slender pedipalps. A dark segment on the tail is sometimes faint or even missing, which can complicate identification.
Most scorpions have a life span of two to six years.
Deathstalker scorpions are very small often tan or reddish colored with small weak pincers. The stinger tip and pincer tips can be darker, almost black colored. Females are larger than males to accommodate reproductive tasks.
Deathstalker scorpions can be found (if one is foolhardy enough to look for one) in dry desert areas and dry scrublands in northern Africa and the Middle East. It prefers a dry climate, and makes its home in natural burrows or under stones.
Scorpions may capture their prey with their pincers but in the case of the Deathstalker, the pincers are fairly weak so a sting must be administered quickly.
The size of the pincers of a scorpion can be a good measure of the potency of its venom. Scorpions with large, powerful pincers have no need for powerful toxins. Scorpions with small, weak pincers need to have strong poisons to subdue their prey and ward off enemies.
The Deathstalker scorpion has the strongest poison of any scorpion. If stung, a person will experience extreme pain, convulsions, paralysis and even death due to heart and respiratory failure.
5. Hydrophis Belcheri