Armadeira (Phoneutria), also known as Aranha-macaco or Aranha-de-bananeira. The common name Armadeira comes from its invariable attitude of attack, with forepaws raised. Originating in the South American region, with a body of 3.5 cm to 5 cm and legs up to 17 cm wingspan. They are highly aggressive and venomous, they produce a neurotoxic venom component which is so potent that only 0.006 mg is enough to kill a mouse. Often come into human settlements looking for food, sexual partners, or even shelter, hiding in clothing and shoes. When disturbed, they sting furiously several times. It is considered the most poisonous spider in the world, according to the Guinness Book, because the potency of its venom neurotoxic action. In Brazil, the second is the spider that causes more accidents, second only to the brown spider, however, unlike the Loxosceles, is extremely aggressive, which is why it is not advisable or allowed its captive breeding.