This is the case with the house spider, the giant house spider and the hobo spider; they all live indoors, but only the latter is a real threat to humans, since its bite can cause necrosis. In order to avoid direct contact with spiders indoors, you can use special sticky traps that will drastically lower the risk of being bitten by a venomous species. Last but not least, certain spider species are a real threat to humans by the damage their venom can do to us. Scientists are the one directly interested in the correct identification of certain spider species, nevertheless, for the average man, knowledge in the field can save one a lot of trouble. When you are able to identify spider species correctly, the risk of getting bitten out of personal negligence is a lot lower; moreover, in case you do get bitten, you can provide valuable information about the species, thus making treatment a lot easier. Unlike most of its brothers, the wolf spider prefers to remain on the ground where it hunts at night; there is no web and no sign that would let you know where you'll find a specimen since the wolf spider desperately tries to stay out of the humans' way. In some parts of the world it is mistaken for the brown recluse spider that is highly venomous, but for the knowledgeable eye the absence of the violin shape of the brown recluse species speaks for itself. In terms of gender relationships, male spiders are famous for being killed right after intercourse, or at least this is the general myth people know. Relatively smaller than the females, the male spiders of certain exotic species are indeed sacrificed for the perpetuation of their breed. Nevertheless, this is not a general rule as in most cases, both males and females survive the encounter. Hives, wheezing, shortness of breath and weakness are the general symptoms associated with anaphylaxis, therefore call 911 right away if you notice any such symptoms. Other systemic reactions to spider bites include leg cramps, leg numbness, headaches, pulse changes, exhaustion and more, they are all serious enough to determine one to call the doctor right away. Even in North America there are three different types of the black widow spider and their classification is made according to the geographical area where they live: there is the northern black widow, the southern black widow and the western black widow; thus the species is widely spread from the south of Canada to Mexico.