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. Keep in mind the fact that these creatures will not attack unless they feel threatened, as a human is no prey for their match. The harm the spider venom can inflict depends on the fierceness with which the spider will defend itself. Furthermore, poisonous spiders are part of balanced ecosystems where they insure a living equilibrium among other species of insects. The curious fact is that lots of brown recluse spider bites have been reported in parts of America where this species does not live. There are other spider varieties to blame for the matter, but none of them causes necrosis, not even the Hobo spider, that is often held responsible. The brown recluse spider bites are the only ones to cause necrosis but in very rare situations and when the immunity of the victim is very low. When you see a brown recluse spider for the first time it is impossible not to notice how much it resembles a violin; it is actually known as the fiddle-back spider or the violin spider for the color pattern it has on the back and bottom areas. Though the color specific to the species is brown, there are yellow and black varieties too, nevertheless, these color patterns are not a general characteristic of the brown recluse spider. It all depends on the body part where you've been bitten; when the spider bites occur on the arm or the leg, tie a bandage right above the bite so as to prevent the spreading of the venom. Nevertheless, too tight a bandage may affect the correct blood flow in the area. A cold cloth pressed on the wound will reduced the swelling and the redness associated with spider bites in general. In the aftermath of such events, the funnel web spider redoubles its level of activity so as to get its life back on track. The size of the species varies from 1.5 to 4.5 centimeters for the body length; they are mono-color, dark brown usually, without any patterns at all. The only distinct element of the male funnel web spider is a swelling on the second leg and the spinnerets located at the end of the abdomen.