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Brown Recluse/Violin Spider

Loxosceles Reclusa

Description:

If you have been bitten, seek immediate medical attention, hospitals usually have anti venom on hand. Reposting from Wikipedia: [Brown recluse spiders are usually between 6–20 mm (1⁄4 in and 3⁄4 in), but may grow larger. While typically light to medium brown, they range in color from cream-colored to dark brown or blackish gray. The cephalothorax and abdomen may not necessarily be the same color. These spiders usually have markings on the dorsal side of their cephalothorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider, resulting in the nicknames fiddleback spider, brown fiddler, or violin spider.] Info on the bite(reposted to save you loading time. Time is valuable in a situation of a bite.) [As suggested by its specific epithet reclusa (recluse), the brown recluse spider is rarely aggressive, and bites from the species are uncommon. In 2001, more than 2,000 brown recluse spiders were removed from a heavily infested home in Kansas, yet the four residents who had lived there for years were never harmed by the spiders, despite many encounters with them. The spider usually bites only when pressed against the skin, such as when tangled within clothes, towels, bedding, inside work gloves, etc. Many human victims report having been bitten after putting on clothes that had not been worn recently, or had been left for many days undisturbed on the floor. However, the fangs of the brown recluse are so tiny they are unable to penetrate most fabric. The bite frequently is not felt initially and may not be immediately painful, but it can be serious. The brown recluse bears a potentially deadly hemotoxic venom. Most bites are minor with no necrosis. However, a small number of brown recluse bites do produce severe dermonecrotic lesions (i.e. necrosis); an even smaller number produce severe cutaneous (skin) or viscerocutaneous (systemic) symptoms. In one study of clinically diagnosed brown recluse bites, skin necrosis occurred 37% of the time, while systemic illness occurred 14% of the time. In these cases, the bites produced a range of symptoms common to many members of the Loxosceles genus known as loxoscelism, which may be cutaneous and viscerocutaneous. In very rare cases, bites can even cause hemolysis—the bursting of red blood cells. Around 49% of brown recluse bites do not result in necrosis or systemic effects. When both types of loxoscelism do result, systemic effects may occur before necrosis, as the venom spreads throughout the body in minutes. Children, the elderly, and the debilitatingly ill may be more susceptible to systemic loxoscelism. The systemic symptoms most commonly experienced include nausea, vomiting, fever, rashes, and muscle and joint pain. Rarely, such bites can result in hemolysis, thrombocytopenia, disseminated intravascular coagulation, organ damage, and even death. Most fatalities are in children under the age of seven or those with a weak immune system. While the majority of brown recluse spider bites do not result in any symptoms, cutaneous symptoms occur more frequently than systemic symptoms. In such instances, the bite forms a necrotizing ulcer that destroys soft tissue and may take months to heal, leaving deep scars. These bites usually become painful and itchy within 2 to 8 hours. Pain and other local effects worsen 12 to 36 hours after the bite, and the necrosis develops over the next few days. Over time, the wound may grow to as large as 25 cm (10 inches). The damaged tissue becomes gangrenous and eventually sloughs away. Validity of necrosis claims It is estimated that 80% of reported brown recluse bites have been misdiagnosed. There is now an ELISA-based test for brown recluse venom that can determine whether a wound is a brown recluse bite, although it is not commercially available and not in routine clinical use. Clinical diagnoses often use Occam's razor principle in diagnosing bites based on what spiders the patient likely encountered and previous similar diagnoses. There are numerous documented infectious and noninfectious conditions that produce wounds that have been initially misdiagnosed as recluse bites by medical professionals, including: Pyoderma gangrenosum Infection by Staphylococcus Infection by Streptococcus Herpes Diabetic ulcers Fungal infection Chemical burns Toxicodendron dermatitis Squamous cell carcinoma Localized vasculitis Syphilis Toxic epidermal necrolysis Sporotrichosis Lyme disease Many of these conditions are far more common and more likely to be the source of necrotic wounds, even in areas where brown recluse spiders actually occur. The most important of these is methicillin-resistant Staphylococcus aureus (MRSA), a bacterium whose necrotic lesions are very similar to those induced by recluse bites, and which can be lethal if left untreated. Misdiagnosis of MRSA as spider bites is extremely common (nearly 30% of patients with MRSA reported that they initially suspected a spider bite), and can have fatal consequences. Reported cases of brown recluse bites occur primarily in Arkansas, Colorado, Kansas, Missouri, Nebraska, Oklahoma, and Texas. There have been many reports of brown recluse bites in California—though a few related species may be found there, none of these are known to bite humans. To date, the reports of bites from areas outside of the spider's native range have been either unverified, or, if verified, the spiders have been moved to those locations by travelers or commerce. Many arachnologists believe that a large number of bites attributed to the brown recluse in the West Coast are either from other spider species or not spider bites at all. For example, the bite of the hobo spider, found in the northwestern United States and southern British Columbia, has been reported to produce similar symptoms as the brown recluse bite. However, the toxicity of hobo spider venom has been called into question as bites have not been proven to cause necrosis. Numerous other spiders have been associated with necrotic bites in medical literature. Other recluse species, such as the desert recluse (found in the deserts of southwestern United States), are reported to have caused necrotic bite wounds, though only rarely. The hobo spider and the yellow sac spider have also been reported to cause necrotic bites. However, the bites from these spiders are not known to produce the severe symptoms that can follow from a recluse spider bite, and the level of danger posed by these has been called into question. So far, no known necrotoxins have been isolated from the venom of any of these spiders, and some arachnologists have disputed the accuracy of spider identifications carried out by bite victims, family members, medical responders, and other non-experts in arachnology. There have been several studies questioning the danger posed by some of these spiders. In these studies, scientists examined case studies of bites in which the spider in question was identified by an expert, and found that the incidence of necrotic injury diminished significantly when "questionable" identifications were excluded from the sample set. (For a comparison of the toxicity of several kinds of spider bites, see the list of spiders having medically significant venom.) Bite treatment First aid involves the application of an ice pack to control inflammation and prompt medical care. If it can be easily captured, the spider should be brought with the patient in a clear, tightly closed container so it may be identified. Routine treatment should include elevation and immobilization of the affected limb, application of ice, local wound care, and tetanus prophylaxis. Many other therapies have been used with varying degrees of success, including hyperbaric oxygen, dapsone, antihistamines (e.g., cyproheptadine), antibiotics, dextran, glucocorticoids, vasodilators, heparin, nitroglycerin, electric shock, curettage, surgical excision, and antivenom. None of these treatments have been subjected to randomized controlled trials to conclusively show benefit. In almost all cases, bites are self-limited and typically heal without any medical intervention. Cases of brown recluse venom traveling along a limb through a vein or artery are rare, but the resulting tissue mortification can affect an area as large as several inches and in extreme cases require excising of the wound. Specific treatments In presumed cases of recluse bites, dapsone is often used effectively for the treatment of necrosis, but controlled clinical trials do not demonstrate similar effectiveness. However, dapsone may be effective in treating many "spider bites" because many such cases are actually misdiagnosed microbial infections. There have been conflicting reports about its efficacy in treating brown recluse bites, and some have suggested it should no longer be used routinely, if at all. Wound infection is rare. Antibiotics are not recommended unless there is a credible diagnosis of infection. Studies have shown that surgical intervention is ineffective and may worsen outcome. Excision may delay wound healing, cause abscesses, and lead to scarring. Anecdotal evidence suggests that the application of nitroglycerin patches can be beneficial. Brown recluse venom is a vasoconstrictor, and nitroglycerin causes vasodilation, allowing the venom to be diluted into the bloodstream and fresh blood to flow to the wound, theoretically preventing necrosis (as vasoconstriction may contribute to necrosis). However, one scientific animal study found no benefit in preventing necrosis, with the study's results showing it increased inflammation and caused symptoms of systemic envenoming. The authors concluded the results of the study did not support the use of topical nitroglycerin in brown recluse envenoming.]

Habitat:

Repost from Wikipedia: [Brown recluse spiders build irregular webs that frequently include a shelter consisting of disorderly thread. They frequently build their webs in woodpiles and sheds, closets, garages, plenum spaces, cellars, and other places that are dry and generally undisturbed. When dwelling in human residences they seem to favor cardboard, possibly because it mimics the rotting tree bark which they inhabit naturally. They have also been encountered in shoes, inside dressers, in bed sheets of infrequently used beds, in clothes stacked or piled or left lying on the floor, inside work gloves, behind baseboards and pictures, in toilets, and near sources of warmth when ambient temperatures are lower than usual. Human-recluse contact often occurs when such isolated spaces are disturbed and the spider feels threatened. Unlike most web weavers, they leave these lairs at night to hunt. Males move around more when hunting than do females, which tend to remain nearer to their webs.]

Notes:

Kill 'em quick. In NC I normally see lighter brown Recluse, but the large fangs are a dead give away. My advice for the willing: catch one in a glass, take photos and videos, share and connect with others. These are nasty mothers. Familiarize yourself with it for your own household safety.

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4 Comments

aanderson1042
aanderson1042 3 years ago

This is a male nursery web spider (Pisaurina mira). I did my PhD work on this species mating behaviors

myrmecophile4
myrmecophile4 3 years ago

Absolutely not a recluse of any sort. This is a male, most likely a Lycosid of some sort.

Connie5
Connie5 4 years ago

I am no expert but I would revisit the ID on this spider. notice the spines on the legs, brown recluse spiders do not have these. Sorry but was looking through photos and ran across this one.

Acts 17_28
Acts 17_28 7 years ago

Wow that's a big one!

hourglasstym
Spotted by
hourglasstym

Asheville, North Carolina, United States

Spotted on Jun 4, 2013
Submitted on Jun 5, 2013

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