The Brown Recluse spider is in the suborder Araneomorphae, which contains 85% of the 45,000 spiders. It is in the family Sicariidae. The Brown Recluse or Loxosceles or Brown Fiddle Spider, is known for its violin or fiddle-like marking on its back. Twenty years ago in Illinois, there were no reports of these spiders being north of Peoria, Illinois. At this time, there are reports that they reach as far north as southern Wisconsin. Another indication of global warming. These spiders love wood piles, basements, attics and dark quiet areas. They multiply quickly and it is not uncommon for them to stay in large groups. A home in Kansas was noted to have over 2000 recluse when they exterminated the area.
For Survive Outdoors, we will approach the venom make up and its effects in a simple format. In short, we know the venom effects erythrocytes which are red blood cells that carry hemoglobin and aid primarily in oxygen change to tissue. It also is lytic and destructive to fat tissue. Hence, when getting bit on areas that have more fat, the lesion becomes more destructive. It does spare muscle though. The venom effects dogs, cats, and rabbits but appears to spare rats and fish. The female Brown Recluse carries more venom. They are often about the size of a quarter and the male has larger pedipalps that are often labeled as fangs from individuals that do not know about spider anatomy. The pedipalps are for holding prey. An interesting fact is the Brown Recluse has three pairs of eyes (six) unlike the majority of spiders having eight.
The skin lesion of the Brown Recluse when it ulcerates is called Necrotic Arachnidism. This skin lesion is the most common, however, all bites do not end in this stage. Most Brown Recluse bites do not ulcerate and the lesion resolves in days. In severe, rare cases, one can have systemic symptoms of renal failure and rarely death.
The bull or blister occurs in about 72 hours after the bite. The bite is commonly not painful as opposed to the black widow. After 2-5 weeks, the area breaks down and the stereotypical crater forms. In severe cases, reconstructive surgery can be done.