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Why the physalia physalis is called 'portuguese man of war'?


A physalia physalis (portuguese man of war).


When we think of danger from the sea, our mind is likely to see a shark with its formidable teeth and its imposing size.

There are, however, some types of innocent-looking marine life that can be even more deadly to the unwary person than the shark.

Among the most interesting of these harmless-looking animal is the Portuguese man-of-war (Physalia physalis).

Travelers visiting the warmer seas for the first time are often amazed to see a flotilla of purple balloons or floats; it is as if they were mysteriously dropped into the sea.

Then as the ship approaches, the whole fleet of bluish balloons may disappear below the waves.

Startling indeed!


Why was it called a Portuguese man of war?



It is thought that the name for this marine animal originated from a comparison with the ancient galleons of Portugal.

Like those ancient war vessels, this legless, finless marvel not only bristles with weapons but it can sail or travel before the wind.

The float or “sail" is quite a marvel in itself.

Strikingly pretty, it may be colored a brilliant azure blue, perhaps with some orange, scarlet or orchid.

The float of a mature animal may be as large as a foot in length and about half as wide and high. 

It is crested on the top by a narrow ridge of air sacs.

These form a “sail" that can be raised or lowered at will, enabling this finless marvel to travel.

If things get too rough on the surface, the man-of-war deflates its float and sinks beneath the waves.

But its “sail” can soon be inflated again by means of a built-in gas-generating mechanism.


How dangerous can it be?



The masses of sting-studded tentacles streaming beneath it, some of which are perhaps forty or fifty feet long, it catches its food.

Woe to the persons who think this animal is but a weak and “spineless” and try to catch it.

Potent is the venom in those thousands of stinging cells.

In its crude form the poison is about 75 percent as poisonous as the venom of the deadly cobra, 'and, like cobra poison, it works on the nervous system.

With its maze of tentacles, the Portuguese man-of-war might be said to have built-in fishing tackle.

If a fish brushes against one of the tentacles, a thousand harpoon-like hypodermics instantly inject a tiny drop of poison.

The victim is paralyzed and the tentacles wrap themselves tightly around the prey, which may be. as large as a mackerel.

Up go the tentacles, like elevators, to deliver the catch to an array of sticky mouths.

Immediately the mouths begin wiggling and squirming to attach themselves to the fish.

Once attached, they begin to expand and spread out around the fish, enwrapping it in a bag, as it were, and then it is digested.

However, at least two animals do not seem to mind close contact with the man of-war.

One is a small bluish fish known as Nomeus, which swims among the potent tentacles with apparent indifference to them and without being harmed.

The other is the loggerhead turtle, which has been known to swim right into an armada of men-of-war and to begin champing away on them, making them a tasty meal.

One observer says that the turtle closes its eyes and gulps the man-of-war whole, perhaps swimming off with tentacles streaming out of its mouth.

Portuguese men-of-war are a familiar sight on Caribbean shores.

Sometimes they are carried by the Gulf Stream and winds along the Atlantic coast of the United States, with some being deposited on the beaches.

There the gas-filled balloons dry up, and when they are stepped on they explode with a loud pop, much to the delight of small boys.

But beware!

Children who jump on these floats barefooted or take hold of the purplish tentacles are asking for trouble.

The tentacles retain their stinging power for a considerable period after the animal has died.

Swimmers must be especially cautious.

They can easily be stung if they get too close to men-of-war.

Getting stung by one is like getting stung by a swarm of bees.

It might be fatal, especially since the swimmer may not be able to make it to shore without help.


How can you treat a Portuguese man o war sting?



When a man-of-war’s tentacles touch human flesh, a red welt is raised like the lash mark of a whip.

The agony from many stings can be excruciating.

Severe stings can cause cramps, nausea and difficulty in breathing.

What will bring some relief as well as put out of commission any undischarged stingers are organic solvents such as alcohol or dilute ammonia, however vinegar is the most currently recommended.

Treat the Portuguese man-of-war with utmost caution.

Give it a wide berth whether you are swimming or walking on the shore.