The 11 Most Dangerous and Poisonous Spiders in the World

Ah, the spiders! These arachnids are certainly not among the most beloved animals by people except on-duty enthusiasts or some biologists. Scattered from every corner of the world are difficult places that are completely absent from these hairy, eight-legged arthropods.

While some species are quite harmless and poison free, there are truly dangerous ones - which can kill brute men with a few bites. With that in mind, here are some of these dreaded examples of spiders that you certainly don't want to approach in any situation (be aware that Brazil and Australia harbor the largest number of poisonous spiders in the world):

1 - Blackfoot Spiders

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These spiders are not very poisonous, although they carry good amounts of poison. Don't worry: If you get stung by them, you are unlikely to die or have serious complications. However, in some more severe cases, their bites can cause necrosis around the bitten site. Fortunately, they only live in the southern United States.

2 - Ornamental Tarantulas

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This type of tarantula is most common near the tropics and in very hot regions. Most tarantulas have no poison whatsoever, and they are considered quite calm - even though their bites are extremely painful. However, it has been reported that some ornamental tarantula bites (Fringed Ornamental Tarantula) caused the victims to fall into a coma.

3 - Chinese Spiders

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They encompass several species and are also known as bird spiders, being very large arthropods that, in some cases, exceed 10 centimeters. Their poison is capable of killing small mammals and children - so care for babies should be redoubled in the regions where they exist (as they usually attack spontaneously). Fortunately, they live only in South Asia.

4 - Rat Spiders

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Popularly known by this name, they can only be found in Australia. The females are totally black and have red fangs - a good warning of the danger there. They are not aggressive, but there have been several cases of bites. Luckily, despite the powerful poison they carry, their bites are often "dry, " meaning they do not release toxins.

5 - Inmate Spiders

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Found in the southern United States and western South America, these spiders are considered quite poisonous. Luckily, we don't have to worry too much about them, as their prey is so small that they can't penetrate the finest cloth clothing - leaving only a few poor victim animals for them.

6 - Red-Backed Spiders

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These arachnids can only be found on Australian land. Relatives of the black widow, they are also very toxic. Before an antidote was developed, the red-backed spiders killed more than 15 people in that country (at least, who were identified as bites by them). Symptoms include dizziness, severe headache, tremors, vomiting, among others.

7 - Black Widow

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The black widow is a species of spider that lives in the Americas, including Brazil, especially on the coasts of continents. The female has a bright black color with a large hourglass-shaped red spot on the ventral surface of the abdomen. Your bite can be fatal and is considered extremely painful.

8 - Funnel Web Spiders

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Typical of Australia, these spiders are known to have very large prey that can reach 2 centimeters. The poison they carry is very powerful, considered one of the most fatal in the world. Although there is an antidote to the poison, it should be applied quickly (in a matter of hours) as people may have permanent sequelae or die.

9 - Sand Spiders

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Fortunately, these arachnids are in desert areas and sparsely inhabited by us humans, such as the deserts of Africa and Asia. The poison is very powerful, with an effect similar to that provided by the recluse spiders, but has no antidote. The bites cause necrosis of the skin tissue and bleeding through the holes in the body and can lead to death.

10 - Brown Spiders

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Popularly known in Brazil, they are famous for their necrotizing and painful bites - which in some cases can lead to irreversible problems if not treated quickly. They are not large (they are between 4 and 6 centimeters) and are very discreet, because they do not usually attack either.

They only sting when they feel confronted, when we come into direct contact with them. The poison is quite powerful, but acts slower, which ensures treatment before limb necrosis.

11 - Armor Spiders

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Weapons are considered the most poisonous and deadly spiders on the planet according to the Guinness Book. And unfortunately, they are extremely common throughout Brazil. They have an average body of 5 centimeters and paws up to 17 centimeters, carrying extremely fatal doses of poison (to be aware, only 0.006 mg is enough to kill a rat).

It is the second spider that causes most accidents in Brazil, behind only brown spiders. However, unlike the latter, the armorers are quite aggressive, attacking on their own accord. More than 7, 000 cases have been reported in the country, but few deaths have occurred, as antidotes are quite common and efficient.

It seems that neither Brazilians nor Australians are very lucky with poisonous spiders, since most of them live in these territories. And you, do you know other species that were not listed? If so, share it in the comments.