10) Huntsman Spiders. These spiders are not dangerous, though they are known to be very aggressive, large, and their bites are painful. Some are territorial and, like a watch dog, will attack anything it sees in ?its territory.? There are several species about the same strength as the Huntsman, most notably the False Black Widows, and Yellow Sac Spiders. Found most commonly in Australia, California, and Japan.
9) True Tarantulas. These are the big hairy spiders famous throughout the world. True tarantulas are also known as New World Tarantulas. These spiders are generally calm and shy, and rarely bite humans. If they do, most normal adults are fine with only mild pain and swelling, though infants and the elderly can be more strongly affected. These tarantulas can be found all over the Americas.
8) Old World Tarantulas. These tarantulas are normally found in Asia and are much more aggressive then their New World cousins. There are several species, though most of them have not been studied closely, one species of Old World Tarantula, the Chinese Bird Spider, has been studied. Its venom is strong on small animals, and it has been credited with one human death, though it is far from being an efficient killer.
7) Hobo Spiders. The Hobo Spider earned its name because it will wander off from its web, and so is more likely to run into people and bite. These spiders are often mistaken for brown recluse spiders, and are usually found in Europe and the Pacific Northwest of the United States. Their bites will cause severe pain, and even tissue death in the area near the bite. This bite should not be fatal for a normal healthy human being.
6) Black Widow Spiders. Black Widows are perhaps the most famous of the North American spiders, and for good reason. Their bites are extremely dangerous, causing severe pain, muscle spasms and contractions and tissue damage. A bite from a widow will often require hospital treatment, and children, the ill, or the elderly can react especially violently in a reaction. With widows, generally only the female spider is considered dangerous. Their most striking feature is a red hour-glass shape.
5) Recluse Spiders. Though not as widely known as the black widow, the recluse spiders may be the most dangerous in the United States, if not all of North America. They like to hide in dark and damp places, which is why most bites come from camping, basements, or closets. They can be found in most of the U.S. Symptoms around the bite include severe pain, tissue death and/or rot, and nerve damage. The pain can take a long time to appear, and the bites have been known to cause ulcers that that eat away at muscle and skin, and occasionally take even years to heal. One unfortunate bite victim was unaware of his bite, but playing soccer weeks later he was kicked in the calf, and his classmates watched in horror as a huge chunk of his leg simply ?blew up? from the impact and fell apart. The long time between the bite and pain gives the poison time to work through the system, which is why many of these spider bites are so severe. These bites must always be treated!
4) Mouse Spiders. No surprise 2 of the 4 most dangerous spiders in the world are from Australia. Mouse spiders are burrowing spiders found in Australia. The mouse spider is strange since its venom is far stronger than recluse and widows, and is even as strong as the most dangerous spiders in the world, <<<but no human deaths have occurred. The theory is that Mouse Spiders give a lot of ?dry bites? that result in no, or less severe, symptoms. Even so, a bite needs to be treated, as the anti-venom for Mouse Spiders are the same as for Funnel Web Spiders, one of the most dangerous in the world.
3) Six Eyed Sand Spiders. Found mostly in Africa. This is the big bad cousin of the recluse spiders and has the same type of poison, only stronger and in larger amounts. It buries itself in the sand and strikes at prey that wanders too close. This spider very rarely comes into contact with humans, and prefers to run and hide rather than fight, but its bite would be lethal to many people.
2) Australian Venomous Funnel-Web Spiders. These are extremely dangerous and extremely aggressive spiders known to frequently bite people. They are big spiders who like to wander and will attack rather than retreat. Many of these spiders can reach two inches in length, and are ?big and fat? to go along with it. Untreated, death will occur anywhere from 15 minutes (in a small child) to 3 days (full grown, healthy adult). Anti-venom was developed, and there are at least 13 recorded cases of death by a Funnel-Web Spider bite, though the numbers may be much higher. This spider is considered by some to be the most dangerous, even more than the spider that makes number one on this list. [I'd worry more about avoiding these if I were you. :Q]
1) Brazilian Wandering Spiders. It seems appropriate that only a spider from the Amazon could dethrone Australia?s most poisonous arachnids. The Brazilian Wandering Spider is distinctive in that every bite hurts, because of the size of the fangs, and some are known to be excruciating. It is known to stand on its hind legs, and raise its front legs and fangs. These spiders get as large as small tarantulas, and can cause death if bites are untreated. Like the Australian Venomous Funnel-Web Spiders, there is an anti-venom, and all bites from this spider most be treated immediately to prevent severe injury and death.