Brazilian Wandering Spider

Brazilian Wandering Spider is a blanket term for the eight species contained within the genus Phoneutria. There are actually relatively few species of spider that pose serious threats to humans.... and these are some of them. Members of this genus are responsible for more human deaths than any other spiders. But remain calm! All members of the genus are native to specific forest and rainforest areas in Central and South America. (Though one did show up in some fruit packaging in Tulsa last year...) They are relatively large spiders on top of being incredibly venomous. Leg spans of the species range between 4 and 5 inches, and body size is 1-2in.

Image from Really Good Magazine

Brazilian Wandering Spiders get their name because they actually move about and hunt actively on the forest floor, rather than residing in nests or webs. This is one of the reasons why they are dangerous to humans. They are nocturnal creatures and thus need a place to hide out during the day. This sometimes leads them to human populated areas, where they may bite if startled.

Though they do not normally build webs, they still have the ability to produce silk, which is used to assist in climbing, to wrap prey, and to build egg sacs. The spiders feed on insects, small reptiles and mice. Their venom is a powerful neurotoxin and contains high levels of serotonin. The toxin shuts down primary functions, while the serotonin moves strait to the brain, causing pain and tremors. The bite also has the side effect of causing painful erections in men. This interesting development has led to pharmaceutical companies doing testing on the venom for ED treatments. There has been an anti-venom for the spider bites since 2004.