Brown Recluse Spider, Fiddleback Spider, Violin Spider
Loxosceles reclusa
Sicariidae (Six-eyed Sicariid Spiders), Order Araneae. Key family characteristics include having only six eyes arranged in three dyads and a distinct lack of heavy patterning.
Physical Description
The brown recluse has a uniform, velvety appearance due to fine, short hairs covering its body. It features a pear-shaped cephalothorax and an elongated oval abdomen without distinct bands or patterns, though a characteristic darker violin-shaped marking is typically visible on the dorsal cephalothorax.
Size Estimate
Body length typically ranges from 6 to 20 millimeters (about 0.25 to 0.75 inches), with a leg span of roughly 24 to 30 millimeters (about 1 inch). The specimen pictured appears to be a medium-to-large adult.
Coloration & Markings
Coloration ranges from yellowish-tan to dark brown. The defining marking is the dark fiddle-shaped band on the cephalothorax with the neck pointing toward the rear. The abdomen is a uniform solid color, lacking spots, stripes, or chevrons.
Web Type
They do not build traditional orb webs to catch prey. Instead, they spin irregular, loose, sticky retreats or webs primarily used as daytime shelters in dark, undisturbed areas, extending trip-lines to detect prey.
Eye Arrangement
Uniquely possesses six eyes arranged in three distinct pairs (dyads): one pair at the front and a pair on each side. This differs from most spiders, which typically have eight eyes.
Leg Characteristics
Legs are long, slender, and uniformly colored without distinct banding, spines, or contrasting rings. They are held somewhat flat and spread out when resting.
Venom & Safety Information
Venom Information
Contains a potent necrotic venom primarily composed of the enzyme sphingomyelinase D. This toxin destroys cell membranes and can cause significant localized tissue destruction, dermonecrotic lesions, and slow-healing wounds.
Medical Significance
Medically significant. While many bites result in minor, self-healing localized irritation, a subset of envenomations leads to severe necrotic skin lesions (loxoscelism) requiring medical intervention. Systemic reactions are rare but possible.
Safety Recommendations
Shake out shoes and clothing before getting dressed, avoid leaving items on the floor, wear gloves when moving stored items in dark spaces, and carefully relocate spiders using a jar and piece of paper if found indoors.
Habitat & Behavior
Habitat & Range
Found primarily in the central and southern United States. They prefer dark, dry, undisturbed microhabitats such as woodpiles, basements, attics, closets, and behind furniture or stored boxes.
Behavior & Temperament
Timid, nocturnal hunters that actively forage at night. They are non-aggressive and typically bite only when trapped against human skin, such as when putting on clothing or rolling over in bed.
Diet & Prey
Carnivorous nocturnal hunters feeding primarily on small insects such as cockroaches, crickets, and silverfish, subduing them with potent venom after a quick ambush.
Seasonal Activity
Most active during the warm spring and summer months, though they remain active year-round indoors in climate-controlled buildings.
Description
The brown recluse is one of North America's most misunderstood yet medically important spiders. Recognized by its telltale violin marking and unique six-eyed arrangement, this shy arachnid prefers solitude in dark, quiet corners. Though capable of delivering a necrotic bite when accidentally compressed against human skin, they are inherently reclusive and avoid confrontation whenever possible.
Key Features
Uniformly colored legs without bands, solid brown abdomen without patterns, distinctive dark violin shape on the cephalothorax, and an arrangement of six eyes in three pairs.
Similar Species
Cellar spiders (Pholcidae), grass spiders (Agelenidae), and male southern house spiders (Kukulcania hibernalis) are frequently mistaken for the brown recluse, but can be distinguished by their prominent eye patterns, body markings, and hairy or spiny legs.
Life Cycle
Females produce several egg sacs containing around 30 to 50 eggs each during the warm months. Spiderlings develop slowly, molting several times, and the species can live for 2 to 4 years.
Ecological Importance
Acts as an effective natural predator that helps control populations of household and outdoor insect pests, fitting into the local food web as an efficient carnivore.
Conservation Status
Not evaluated by the IUCN, but populations are widespread, abundant, and stable throughout their native geographic range.
Interesting Facts
Brown recluses can survive for months without food or water in extreme conditions. Their venom is specialized primarily to quickly immobilize hard-shelled arthropod prey.
Photography Tips
Use a macro lens with natural or diffused lighting from a safe distance of at least a foot. Capture a top-down view to clearly show the cephalothorax markings and eye arrangement without disturbing the spider.
Identified: 2026-09-21T21:27:12.349324