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What the sources say

Brown RecluseLoxosceles reclusa

Every figure, record and mechanism on the Brown Recluse profile was written from a source, and this is the working table behind it: 62 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Edwards

Edwards. Brown Recluse Spider, Loxosceles reclusa Gertsch & Mulaik (Arachnida: Araneae: Sicariidae). Featured Creatures, UF/IFAS Extension, University of Florida.

The page saysExtreme
The source saysReactions to a bite vary from no noteworthy symptoms to severe necrosis or systemic effects.Note: stats.dangerLevel; capability: severe necrosis or systemic effects
The page saysAdults are about 7 to 12 mm long
The source saysranging from about 7 to 12 mm in body length
The page saysfemales average about 9 mm compared with about 8 mm for males
The source saysAdult females average slightly larger, about 9 mm compared to about 8 mm for adult males.
The page saysIn one Arkansas study of 626 spiders, most were found in buildings and outbuildings, especially in boxes and among papers
The source saysthey recorded the habitat of 626 brown recluse in Arkansas found from May 1962 to December 1964. Most (430) were found in buildings and outbuildings, especially in boxes and among papers
The page saysIts prey includes rather dangerous animals such as other spiders and ants
The source saysPrey consists of a variety of other arthropods, including rather dangerous prey like other spiders and ants.
The page saysIt strikes these with a sudden lunge and bite, then backs away at once while the venom paralyzes them
The source saysThe attack consists of a sudden lunge and bite, ... after which the brown recluse immediately backs away (personal observation). The venom acts rapidly to paralyze the prey
The page saysAfter the prey is overcome, it moves in to feed
The source saysAfter the prey is overcome by the venom, the brown recluse moves in to feed.
The page saysThe maximum age from emergence to death was 894 days for a female and 796 for a male
The source saysMaximum age for a brown recluse from emergence to death was 894 days for a female, 796 for a male.
The page saysA major part of the venom is sphingomyelinase D, which causes hemolysis, the destruction of red blood cells
The source saysA major venom component is sphingomyelinase D, which causes hemolysis (destruction of red blood cells).
The page saysWithin 10 minutes of the injection, the capillaries around the bite constrict
The source saysWithin 10 minutes of venom injection, there is a constriction of capillaries around the site of the bite.
The page saysIf the skin turns purple, it then turns black as cells die
The source saysIf the skin turns purple, it will then turn black as cells die.
The page saysEventually the dead core falls away and leaves a deep pit that gradually fills with scar tissue
The source saysEventually the necrotic core falls away, leaving a deep pit that gradually fills with scar tissue.
The page saysReactions run from no noteworthy symptoms to severe necrosis
The source saysReactions to a bite vary from no noteworthy symptoms to severe necrosis or systemic effects.
The page saysLess than 1% of cases bring the blood problems of severe systemic loxoscelism
The source saysThe presence of sustained coagulopathy with hemolysis indicates severe systemic loxoscelism. Fortunately, less than 1% of cases exhibit these symptoms.
The page saysnone of the deaths attributed to it had been proven to be its doing
The source saysAnderson (1998) noted, however, that none of the fatalities were proven to have been caused by a brown recluse spider.
The page saysin 1998 a physician who had worked on recluse bites and venom for 40 years
The source says(Anderson 1998) [Dr. Philip C. Anderson is a physician and medical researcher who has worked on brown recluse bites and venom for 40 years]
The page saysBites usually happen only when the spider is trapped against skin, such as when a sleeper rolls onto it or someone puts on clothes it has crawled into
The source saysBrown recluse spiders usually bite only when they become trapped next to the victim's skin. Bites occur either when sleeping humans roll onto the spider or put on clothes into which the spider has crawled
The page saysIn typical cases, symptoms begin two to six hours after the bite
The source saysTypical symptoms are as follows. Symptoms start two to six hours after the bite.
The page saysWithin 12 to 24 hours the wound usually shows whether it will die back, because it turns purple
The source saysBy 12 to 24 hours, it is usually apparent if a Loxosceles wound is going to become necrotic because it turns purple in color
The page saysIf no necrotic signs have appeared by 48 to 96 hours, they will not develop
The source saysif necrotic symptoms do not express by 48 to 96 hours, then they will not develop
The page saysInsects, spiders and other arthropods
The source saysPrey consists of a variety of other arthropods, including rather dangerous prey like other spiders and ants.Note: stats.diet
The page saysOutside its range, diagnoses outrun the spider
The source saysthe chance of interaction between brown recluse spiders and people in Florida is close to nil, agreeing with Vetter's (2000) assessment of reported brown recluse bites outside the natural range of the spider

Source
02

Jones 2004

Jones (2004). Brown Recluse Spider. Ohio State University Extension fact sheet HYG-2061-04, copy hosted by Spartanburg County Public Health.

The page saysA six-eyed night hunter with a violin marking
The source saysWhereas most spiders have eight eyes, recluse spiders have six eyes that are arranged in pairs in a semicircle on the forepart of the cephalothoraxNote: tagline
The page saysvenom that can kill the tissue around a bite
The source saysothers experience immediate or delayed effects as the venom kills the tissues (necrosis) at the site of the biteNote: tagline
The page saysVenom that can kill the tissue around its bite
The source saysothers experience immediate or delayed effects as the venom kills the tissues (necrosis) at the site of the biteNote: stats.superpower
The page saysMost spiders have eight eyes. Recluse spiders have six, arranged in pairs in a semicircle on the forepart of the cephalothorax
The source saysWhereas most spiders have eight eyes, recluse spiders have six eyes that are arranged in pairs in a semicircle on the forepart of the cephalothorax
The page saysthe fused head and thorax
The source sayscephalothorax (fused head and thorax)
The page saysSix eyes and a violin
The source saysrecluse spiders have six eyes that are arranged in pairsNote: heading
The page saysSix eyes
The source saysrecluse spiders have six eyes that are arranged in pairsNote: blockquote lead
The page saysAdults often live about one to two years
The source saysAdult brown recluse spiders often live about one to two years.
The page saysThat is necrosis, or tissue death
The source saysthe venom kills the tissues (necrosis) at the site of the bite
The page saysFatalities are extremely rare
The source saysFatalities are extremely rare
The page saysNecrotic wounds can also come from bacteria, viruses, fungi and other arthropods
The source saysNecrotic wounds can result from a variety of agents such as bacteria ( Staphylococcus, "flesh-eating" Streptococcus , etc.), viruses, fungi, and arthropods
The page saysa wrong diagnosis can delay proper care
The source saysMisdiagnosis of lesions as brown recluse bites can delay appropriate care.
The page saysAdults can survive about 6 months without food or water
The source saysThey can survive long periods of time (about 6 months) without food or water.
The page saysThe vast majority of bites heal without severe scarring
The source saysThe vast majority of brown recluse bites heal without severe scarring
The page saysMost spiders have eight eyes
The source saysWhereas most spiders have eight eyes, recluse spiders have six eyes
The page saysRecluse spiders have six, arranged in pairs in a semicircle on the forepart of the cephalothorax, the fused head and thorax
The source saysrecluse spiders have six eyes that are arranged in pairs in a semicircle on the forepart of the cephalothorax
The page saysVenom that kills tissue
The source saysthe venom kills the tissues (necrosis) at the site of the biteNote: heading

Source
03

Potter

Potter. Brown Recluse Spider (ENTFACT-631). University of Kentucky Department of Entomology.

The page saysA six-eyed night hunter with a violin marking
The source saysThe brown recluse hunts at night seeking insect prey, either alive or dead.Note: tagline
The page saysA six-eyed night hunter with a violin marking
The source saysFor laypersons, the most distinguishing feature of a brown recluse is a dark violin-shaped mark on its backNote: tagline
The page saysSouth central and Midwestern United States
The source saysis found throughout the south central and Midwestern United StatesNote: stats.habitat
The page saysInsects, spiders and other arthropods
The source saysThe brown recluse hunts at night seeking insect preyNote: stats.diet
The page saysA dark violin shape sits on its back, with the neck of the violin pointing toward the rear of its body
The source saysa dark violin-shaped mark on its back, with the neck of the violin pointing toward the rear (abdomen) of the spider
The page saysWith its legs stretched out, it is about the size of a US quarter
The source saysadult brown recluse spiders with legs extended are about the size of a U.S. quarter
The page saysIt lives across the south central and Midwestern United States
The source saysis found throughout the south central and Midwestern United States
The page saysOutdoors it shelters under rocks, logs, woodpiles and debris
The source saysIn nature, brown recluse spiders live outdoors under rocks, logs, woodpiles and debris.
The page saysIt is also well adapted to living indoors
The source saysThe spider is also well adapted to living indoors with humans.
The page saysBy day the brown recluse hides in a dark, secluded retreat, which it often lines with irregular webbing
The source saysDuring daylight hours, brown recluse spiders typically retreat to dark, secluded areas. They often line their daytime retreats with irregular webbing
The page saysAt night it hunts insect prey, alive or dead, and it does not use a web to capture food
The source saysThe brown recluse hunts at night seeking insect prey, either alive or dead. It does not employ a web to capture food
The page saysthe majority stay local and heal within 3 weeks
The source saysThe majority of brown recluse spider bites remain localized, healing within 3 weeks without serious complication or medical intervention.
The page saysThe species is native to the south central and Midwestern states, and spiders found outside that range are rare
The source saysfound throughout the south central and Midwestern United States. ... Recluse spiders are rare outside their native range.
The page saysA few may ride along in boxes or furnishings, but infestations seldom become established there
The source saysOccasionally, one or a few spiders may be transported to a non-native area in boxes or furnishings, but infestations seldom become established.
The page saysThe brown recluse is a small spider with one striking mark
The source saysFor laypersons, the most distinguishing feature of a brown recluse is a dark violin-shaped mark on its backNote: size in the next sentences: 7 to 12 mm body length (uf-recluse)
The page saysA night hunter with no web trap
The source saysThe brown recluse hunts at night seeking insect prey, either alive or dead. It does not employ a web to capture foodNote: heading
The page saysThe brown recluse hides in a dark retreat by day, hunts at night
The source saysDuring daylight hours, brown recluse spiders typically retreat to dark, secluded areas. They often line their daytime retreats with irregular webbingNote: vibe.reason
The page saysis well adapted to living indoors
The source saysThe spider is also well adapted to living indoors with humans.Note: vibe.reason

Source
04

Animal Diversity Web, University of Michigan

Loxosceles reclusa. Animal Diversity Web, University of Michigan.

The page saysNot Evaluated
The source saysIUCN Red List [Link] Not EvaluatedNote: stats.conservationStatus. Checked 2026-09-29: GBIF and Crossref show no Red List assessment for Loxosceles reclusa; the ADW page lists it as Not Evaluated.

Source
05

Vetter & Barger 2002

Vetter & Barger (2002). An Infestation of 2,055 Brown Recluse Spiders (Araneae: Sicariidae) and No Envenomations in a Kansas Home: Implications for Bite Diagnoses in Nonendemic Areas. Journal of Medical Entomology.

The page saysIn one occupied Kansas home, 2,055 brown recluses were collected over 6 months, and no envenomations of the inhabitants occurred
The source saysDuring a 6-mo period, 2,055 brown recluse spiders, Loxosceles reclusa Gertsch and Mulaik, were collected in a 19th-century-built, currently occupied home in Lenexa, KS. ... Despite these infestations, no envenomations of the inhabitants of these three homes occurred.

Source
06

Vetter, Edwards & James 2004

Vetter, Edwards & James (2004). Reports of Envenomation by Brown Recluse Spiders (Araneae: Sicariidae) Outnumber Verifications of Loxosceles Spiders in Florida. Journal of Medical Entomology.

The page saysIn Florida, medical personnel diagnosed 124 brown recluse bites in 6 years, across 31 of the state's 67 counties
The source saysMedical personnel diagnosed 124 brown recluse spider bites from 31 of Florida's 67 counties in 6 yr.
The page saysIn 100 years, only 11 finds of about 70 Loxosceles spiders had been made in 10 counties
The source saysonly 11 finds of approximately 70 Loxosceles spiders have been made in 10 Florida counties in 100 yr
The page saysBlamed for wounds it did not make
The source saysFlorida does not have sufficient widespread populations of Loxosceles spiders to warrant consideration of brown recluse spider envenomation as a probable etiology of dermonecrosisNote: heading

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.