animalia kingdom
Arthropod phylum
Arachnid class
Araneae Order
Spiders are arthropods belonging to the Arachnida Class, the same as scorpions, with a body divided into cephalothorax and abdomen, with four pairs of legs, appendages, chelicerae and spinnerets. Therefore, they are not insects, as they do not belong to the Order Insecta.
The Order Araneae, to which spiders belong, is one of the largest animal groups in terms of its diversity. These predators are distributed all over the world, existing in our country more than 12 thousand species. They are very important in the population control of several invertebrates – including insects.
Because most species build webs, they play very surprising strategies. of predation, and also possessing venom, are animals that, in addition to curiosity, arouse fear in people. However, accidents are not that frequent, and occur when they feel threatened. Therefore, it is necessary to be very careful, for example, when putting on a shoe without first checking that there is nothing inside it.
There are three genera of venomous spiders found in Brazil: Phoneutria, Latrodectus and Loxosceles; housing the armadeiras, black widows and brown spiders, respectively. Based on these data, another important piece of information is that crab spiders do not inoculate venom.
As for the gunships, they belong to one of the most aggressive groups. At the moment of attack, they raise their front legs and, resting on their hind legs, jump towards the target. Most accidents involving spiders are caused by animals belonging to this genus, causing severe pain, redness, small swelling and local sweating.
Black widows have this name because at the end of mating, in many species of the group, the female rips off the male's head and devours him. Its venom causes intense pain, and can cause, in some situations, sweating, tachycardia, hypertension and muscle contractions and, in severe situations, anaphylactic shock. In men, it can cause priapism: a persistent and often painful erection.
Brown spiders are small in size but have a very potent venom. They are not aggressive, but attack when they are pressed against the body, forming a difficult wound. scarring and which can cause necrosis if the injured person does not take the necessary measures clinics. Some patients also develop anemia and even kidney failure, revealing the importance of seeking medical help.
For all these cases of araneism, there is a serum, whose main form of use is intravenous. The use of antihistamines may be recommended in order to prevent against allergic reactions.
By Mariana Araguaia
Graduated in Biology
