- Redback Spider
The Redback Spider resides in the same family as the Black Widow, and is very toxic as well. It normally resides in Australia, and can easily be noticed from the dark red stripe running down its back. Serious symptoms of the bite are known to include seizures, comas, or even respiratory failure.
- Black Widow
When thinking of venomous spiders, most of us imagine this as the first thing that comes to our mind. However, a quite unknown fact about the Black Widow is that it actually eats its male partner after having intercourse. The Black Widow's Bite is known to cause lactrodectism, or muscle spasms, throughout the body. It only needs a dosage of 0.0002mg/kg of venom in order to kill its prey.
- Sydney Funnel-web Spider
This is known as one of the most venomous spiders on Earth. Instead of giving smaller bites, a Sydney Funnel-web Spider is known to always inject a full amount of venom into their victim. Atracotoxin, a chemical in its venom compound, is very dangerous to primates, including humans. One child died within 15 minutes of receiving a bite from this hazardous spider.
- Six-eyed Sand Spider
Although still very dangerous, this spider is known to not usually live near humans. It's not very aggressive either, meaning that bites are mostly uncommon. It's a cousin of recluses, another species of spider, although the venom is much more potent. Their bite is known to cause necrosis, blood clots, and extreme bleeding which may even result in death.
- Brazilian Wandering Spider
In 2010, the Guinness World Records named this as the most venomous spider on Earth. It is extremely aggressive, and its vicious bite causes breathing problems and eventually asphyxiation. Oddly, its venom also causes priapism, which causes males to have long-lasting erections. Because of this, its venom is being studied in order to possibly combat Erectile Dysfunction Syndrome. Even after receiving an antidote, humans have still been known to perish after being bitten by this dangerous creature.