Brown Recluse Spider, Fiddleback Spider, Violin Spider
Loxosceles reclusa
Sicariidae (Six-eyed Sicariid Spiders), Order Araneae. Key family characteristics include the presence of only six eyes arranged in three dyads and a tendency to inhabit dark, undisturbed areas.
Physical Description
The brown recluse has a uniform light brown to yellowish-tan cephalothorax and abdomen. The cephalothorax features a distinct darker violin-shaped marking with the neck pointing backward. The body is finely covered with short, fine hairs rather than spines.
Size Estimate
Body length is typically 6 to 20 millimeters (0.24 to 0.79 inches), with a leg span extending up to 20 to 30 millimeters. This specimen appears to be an adult or subadult.
Coloration & Markings
Uniform fawn to dark brown coloration with no prominent abdominal patterns or bands on the legs. The signature diagnostic mark is the dark violin shape on the dorsal carapace.
Web Type
Irregular, sticky retreat webs spun in dark corners, under objects, or inside wall voids, used primarily as a shelter rather than to actively catch flying prey.
Eye Arrangement
Six eyes arranged in three distinct pairs (dyads): one pair centrally located and a pair on each side, which is a key diagnostic feature for the Sicariidae family.
Leg Characteristics
Long, thin, delicate legs of a uniform color lacking prominent spines, banding, or clubbing, typically held spread out flat against the surface when resting.
Venom & Safety Information
Venom Information
Contains a potent necrotic venom primarily composed of the enzyme sphingomyelinase D, which destroys cell membranes and can cause localized tissue destruction (dermonecrosis).
Medical Significance
Medically significant. While many bites result in minor localized irritation, severe envenomation can lead to deep necrotic ulcers requiring medical attention, though systemic reactions are rare.
Safety Recommendations
Wear gloves when moving stored items in basements or attics, shake out shoes before wearing, and gently relocate spiders outdoors using a glass and stiff paper if found inside.
Habitat & Behavior
Habitat & Range
Found primarily in the Midwestern and South-Central United States. Prefers dark, warm, dry microhabitats such as woodpiles, basements, attics, closets, and behind furniture.
Behavior & Temperament
Noxious, reclusive, and non-aggressive. They actively forage at night and retreat rapidly when disturbed, biting only when trapped against human skin.
Diet & Prey
Insects and other arthropods, hunted actively at night rather than captured via an orb web.
Seasonal Activity
Most active during spring and summer months, though indoor specimens remain active year-round in heated buildings.
Description
The brown recluse is one of North America's most misunderstood spiders. Known for its characteristic violin marking, it prefers solitude in dark, undisturbed crevices. While venomous, it rarely bites unless compressed against the skin.
Key Features
Six eyes in three pairs, a distinct violin-shaped marking on the cephalothorax, uniform brown legs without bands, and a lack of bright abdominal patterns.
Similar Species
Cellar spiders (Pholcidae), male southern house spiders (Kukulcania hibernalis), and wolf spiders (Lycosidae). Distinguish them by examining the eye arrangement and the violin marking.
Life Cycle
Females produce several egg sacs containing around 50 eggs each during the warmer months. Spiderlings molt multiple times, reaching maturity in about a year and living up to 2 to 4 years.
Ecological Importance
Acts as an effective natural predator regulating local insect populations in woodland and domestic environments.
Conservation Status
Not evaluated by the IUCN, but populations are secure and widespread within its native range.
Interesting Facts
Brown recluse spiders can survive for months without food or water in extremely dry environments and possess silk that is remarkably fine compared to web-weavers.
Photography Tips
Use macro lenses with adequate natural lighting or a diffused flash. Focus sharply on the carapace to capture the violin pattern and the eye arrangement safely from a distance.
Identified: 2026-10-06T18:05:45.359311