Brown Recluse Spider, Violin Spider, Fiddleback Spider
Loxosceles reclusa
Sicariidae (Six-eyed Sicariid Spiders), Order Araneae. Key family characteristics include having only six eyes arranged in distinct dyads.
Physical Description
The brown recluse features a uniform light brown to dark brown body with a distinctly violin-shaped marking on its cephalothorax, pointing toward the abdomen. The body is relatively smooth and finely haired, lacking conspicuous spines or strong banding on the legs.
Size Estimate
Body length is typically 6 to 20 millimeters (0.24 to 0.79 inches), with a leg span ranging from 20 to 30 millimeters (0.79 to 1.18 inches). The specimen shown appears to be an adult.
Coloration & Markings
Uniformly fawn to dark brown coloration across the cephalothorax, abdomen, and legs. The hallmark feature is the dark violin shape on the dorsal cephalothorax. The abdomen lacks distinct patterns, stripes, or colorful markings.
Web Type
Irregular, sticky cobwebs constructed in dark, secluded locations rather than symmetrical orb webs. These webs serve primarily as daytime retreats rather than active traps.
Eye Arrangement
Uniquely possesses six eyes arranged in three pairs (dyads): one median pair and two lateral pairs. This contrasts with the typical eight-eyed arrangement of most true spiders.
Leg Characteristics
Long, thin, delicate legs of uniform color without prominent spines or banding. They often spread wide in a sprawling posture when resting or startled.
Venom & Safety Information
Venom Information
Contains a potent necrotic venom containing the enzyme sphingomyelinase D, which destroys cell membranes, potentially leading to dermonecrotic lesions.
Medical Significance
Medically significant. While many bites result in minor localized irritation, severe envenomation can cause localized tissue necrosis (necrotic arachnidism), ulceration, and systemic symptoms requiring medical evaluation.
Safety Recommendations
Shake out shoes and clothing left on the floor, wear gloves when handling stored items, seal entry points, and seek medical attention if a bite causes expanding lesions.
Habitat & Behavior
Habitat & Range
Native to the central and southern United States, ranging from the Midwest down to Texas and eastward to Georgia. Prefers dark, dry, undisturbed microhabitats such as woodpiles, basements, closets, and attics.
Behavior & Temperament
Nocturnal active hunters that forage away from their retreat at night. Generally non-aggressive, they bite defensively only when trapped against the skin (e.g., inside clothing or shoes).
Diet & Prey
Mainly feeds on small insects such as cockroaches, crickets, and other soft-bodied arthropods captured via active hunting or ambushing near its retreat.
Seasonal Activity
Most active during spring, summer, and fall. During winter, they typically seek shelter indoors or in protected outdoor crevices to overwinter.
Description
The brown recluse is a reclusive, nocturnal hunter known for its characteristic violin marking. While medically significant, it prefers to avoid human contact, typically hiding in quiet, undisturbed spaces.
Key Features
Six eyes in three dyads, uniform brown coloration without spines on legs, and the distinctive dark violin-shaped marking on the cephalothorax.
Similar Species
Cellar spiders (Pholcidae), grass spiders (Agelenidae), and male southern house spiders (Kukulcania hibernalis). Distinguished by examining eye count, violin marking, and leg spination.
Life Cycle
Females produce several egg sacs containing around 50 eggs each during the warm months. Spiderlings mature through multiple molts over a year, and adults can live for 2 to 4 years.
Ecological Importance
Acts as an effective predator of household and garden insect pests, helping regulate populations of cockroaches and other arthropods.
Conservation Status
Not evaluated by the IUCN, but populations are widespread, secure, and locally abundant within their native range.
Interesting Facts
Can survive for months without food or water in extreme environments and often seeks refuge inside cardboard boxes, shoes, and folded clothing.
Photography Tips
Photograph from a safe distance using macro lenses and good natural or diffused lighting. Capture dorsal views of the cephalothorax to clearly show the violin pattern and eye arrangement.
Identified: 2026-08-30T15:38:49.816178