One identification method used by scientists consists in checking how many pairs of eyes the species has; the brown recluse spider has only three pairs of eyes, unlike most other spiders that have four. Two eyes are located in a median position while the other four are placed on the sides of the body. Every year around August and September the hobo spider males are incredibly active, and it is during this time of the year that most bites are reported. The shape of the web woven by the hobo spider is truly unique, it consists of a very dense silk sheet which is usually curved upwards so that insects that come from above the structure may fall into it. There are several other varieties related to the black widow spider; they live in South Africa and Australia, and the major difference from the North American black one is of color: they are red and brown. 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. Sometimes a spider bite can have very few local marks and it is only identified by the symptoms. The physical reactions to a spider bite are usually classified into local and systemic; the former can be treated at home right after the occurrence of the accident, whereas the latter often require professional medical treatment in order to reduce the reaction of the body to the venom. The truth is somewhere in between: the camel spider lives in the Middle East countries, and it has become known in the United States and the rest of world after US troops have come across some specimens. The camel spider is even falsely called a spider, since the species is cataloged under a different name in the zoological categories. The favorite pray of trapdoor spiders includes grasshoppers, moths, crickets, but they don't back off when it comes to having small birds and scorpions for their meals too. The size of trapdoor spiders is not larger than three centimeters for the body, with the females clearly dominating the males in this respect.