The Most Dangerous Spiders in the World

When listing the top ten most dangerous spiders (based on how common the spider is, and how deadly its venom is to humans), how many do you think live in Arizona? Really? Which ones?

#2. THE BLACK WIDOW SPIDER

Black widows are notorious spiders identified by the colored, hourglass-shaped mark on their abdomens. Several species answer to the name, and they are found in temperate regions around the world. Approximately 5% of the reported bites were fatal prior to the intervention of the Widow spider antivenom. One of their favorite haunts is an old-fashioned outhouse. 63 deaths were reported in the U.S. between 1950 and 1959, most of which occured in or around a woodpile or outhouse. But with the modernization of home plumbing and heating, Black Widow bites are now very rare.

This spider's bite is much feared because its venom is reported to be 15 times stronger than a rattlesnake's. In humans, bite produce muscle aches, nausea and a paralysis of the diaphragm that can make breathing difficult; however, contrary to popular belief, most people who are bitten suffer no serious damage-let alone death. But bites can be fatal, usually to small children or the elderly. Fortunately, fatalities are fairly rare; the spiders are non-aggressive and bite only in self-defense, such as when someone accidentally sits on them.

#4 THE BROWN RECLUSIVE SPIDER

The Brown Recluse Spider, also known as "violin spiders," "fiddlers," or "fiddlebacks," from the dark violin-shaped marking on the head are slow moving, retiring spiders that wander about in dim areas. They often den in footwear, clothing and beds, and are then easily trapped against someone's skin by clothing, bed sheets, etc.-leading to the spider's bite.

Most encounters with this spider occur from moving boxes or rooting about in closets or under beds. The range of the Brown Recluse in the U.S. is mostly restricted to the Mid-west, South and Southeast. However, a number of related recluse spiders are found in southern California and nearby areas, including Arizona.

The bite of a Brown Recluse is extremely venomous, and has led to fatalities through massive tissue loss and the subsequent infection. Deaths from Brown Recluse spiders have been reported only in children younger than seven years.

#9 THE WOLF SPIDER

The Wolf Spider is a member of the Lycosidae family, and there are around 125 species found the U.S. and about 50 species found in Europe. A full grown Wolf Spider is typically a half an inch to two inches in length. They are hairy and are usually brown or gray with various stripe-like markings on their backs. They eye arrangement of the wolf spider is one of its most interesting features, with four small eyes in the bottom row, followed by two large eyes in the middle row, and two medium eyes in the top row. They received the name wolf spider due to an early belief that the spiders would actually names for the wolf spider are the Ground Spider and the Hunting Spider. Wolf Spiders do not make webs, but actively hunt for their prey.

Even though the Wolf Spider is poisonous, its venom is not lethal. This spider is not known to be aggressive; however, they will bite if they feel like they are in harm or danger. They also move extremely fast when they are disturbed. If bitten by a Wolf Spider, the wound should not be bandaged but an ice pack should be placed on the bite to reduce swelling. If necessary, the victim should avoid any movement or increased heart rate. It is extremely important to see medical attention if bitten by a Wolf Spider.