7. Brown recluse spider, violin spider, fiddleback spider (Loxosceles reclusa)
LD50 value: 0.48
These spiders are found mostly throughout the south-central US, but are spread in Canada also. They can sometimes be found living in colonies of several thousand specimens. Although these spiders are somewhat common and highly venomous, bites in humans are not fatal, and even less than 10% are considered to be the “serious category” of bites.
