Brown Recluse, Fiddleback Spider, Violin Spider
Loxosceles reclusa
Sicariidae (Six-eyed Sand Spiders), Order Araneae
Physical Description
A medium-sized spider with a smooth, finely-haired cephalothorax. The abdomen is oval-shaped and uniformly colored with no patterns. They are known for their slender build and lack of thick spines on the legs.
Size Estimate
Body length 6-12mm (1/4 to 1/2 inch) with a leg span approximately the size of a US quarter or slightly larger (2-3cm).
Coloration & Markings
Light to medium brown base color. The most distinguishing mark is a dark brown 'violin' or 'fiddle' shape on the dorsal side of the cephalothorax, with the neck of the violin pointing toward the abdomen.
Web Type
Tangle/Sheet web. They build irregular, grayish-white, sticky webs in undisturbed corners, typically used as a retreat rather than for active prey capture.
Eye Arrangement
Six eyes arranged in three pairs (dyads) in a semi-circular pattern: one medial pair and two lateral pairs. They lack the eight eyes common to most spiders.
Leg Characteristics
Long, thin, and uniformly colored legs. They lack conspicuous banding or thick spines, though they are covered in very fine hairs.
Venom & Safety Information
Venom Information
Hemotoxic/Cytotoxic venom containing sphingomyelinase D. It is medically significant and can cause skin necrosis (tissue death) and, rarely, systemic reactions.
Medical Significance
Medically significant. Most bites heal without complication, but some result in necrotic ulcers. Seek medical attention if a bite is suspected, especially if a lesion develops with a 'bullseye' appearance.
Safety Recommendations
Shake out shoes and clothing stored in dark areas. Reduce clutter in basements and garages. Use glue traps for monitoring and wear gloves when moving stored items. If bitten, apply ice and seek medical evaluation.
Habitat & Behavior
Habitat & Range
Primarily found in the Central and Midwestern United States. They prefer dark, dry, undisturbed areas such as woodpiles, sheds, basements, closets, and behind furniture.
Behavior & Temperament
Reclusive and non-aggressive. They are nocturnal hunters that prefer to flee or hide rather than bite. Bites usually occur when the spider is trapped against skin (e.g., inside clothing or bedding).
Diet & Prey
Carnivorous; hunts small insects like crickets, silverfish, and cockroaches. They are active hunters that leave their web at night to search for prey.
Seasonal Activity
Most active from March through October. They tend to overwinter in wall voids or insulated areas during colder months.
Description
The Brown Recluse is one of the most misunderstood spiders in North America. While its necrotic venom is potent, it is a shy creature that avoids human contact whenever possible. It is identified by its violin-shaped marking and its unique six-eye configuration.
Key Features
Violin marking on the cephalothorax, six eyes in three pairs, uniformly colored legs without bands, and a uniformly colored abdomen.
Similar Species
Often confused with Wolf Spiders (Lycosidae), House Spiders (Tegenaria), or Cellar Spiders (Pholcidae). None of these have the same violin marking and six-eye arrangement.
Life Cycle
Females produce 1-5 egg sacs containing 40-50 eggs each. Spiderlings reach maturity in about a year and adults can live for 2 to 4 years.
Ecological Importance
Provides significant natural pest control by preying on household insects like silverfish and moths, playing a role in maintaining ecological balance in indoor and outdoor microhabitats.
Conservation Status
Not evaluated by IUCN; generally considered common and stable within its native range.
Interesting Facts
They can survive for months without food or water. Unlike many spiders that use webs to catch food, the Recluse is an active roamer that searches for its meals.
Photography Tips
A clear macro shot of the 'violin' marking and/or the eye arrangement is essential for definitive identification. Ensure the spider is still and use a high f-stop for depth of field.
Identified: 2026-06-22T16:31:30.770150