Brown Recluse Spider, Violin Spider, Fiddleback Spider
Loxosceles reclusa
Sicariidae (Six-Eyed Sicariid Spiders), Order Araneae
Physical Description
The spider has a uniform light brown to tan cephalothorax featuring a distinctive darker violin-shaped marking with the neck pointing toward the rear. The abdomen is oval, covered in fine, short hairs, and generally uniformly colored without conspicuous patterns. Legs are long, slender, and uniformly colored without bands or spines.
Size Estimate
Body length typically ranges from 6 to 20 millimeters (0.24 to 0.79 inches), with a leg span extending up to 25 to 30 millimeters (1 inch).
Coloration & Markings
Colors range from light tan to dark brown. The primary diagnostic marking is the dark violin-shaped pattern on the dorsal carapace. The abdomen ranges from cream to dark brown depending on recent feeding, lacking stripes, bands, or chevrons.
Web Type
Irregular, loose, sticky retreat web usually built in dark, undisturbed areas such as under furniture, in closets, basements, or woodpiles, serving primarily as a daytime shelter rather than an active trap.
Eye Arrangement
Arranged in six eyes grouped in distinct dyads (pairs)—one pair anteriorly and two lateral pairs—which is a defining characteristic of the family Sicariidae, differing from the typical eight-eyed pattern of most spiders.
Leg Characteristics
Long, slender, spindly legs lacking any prominent spines, banding, or strong coloration contrasts. They are held in a sprawling posture when at rest.
Venom & Safety Information
Venom Information
Contains a potent necrotic venom containing the enzyme sphingomyelinase D, which can cause tissue destruction, dermonecrotic lesions, and, in rare systemic cases, severe systemic reactions known as locoscelism.
Medical Significance
Medically significant. Bites can result in a slow-healing necrotic wound that develops a central blister and ulceration. While many bites resolve without significant complications, medical attention is recommended if skin lesion formation occurs.
Safety Recommendations
Inspect and shake out stored clothing, shoes, and bedding before use. Seal cracks and crevices in homes, wear gloves when moving firewood or stored items, and carefully relocate specimens outdoors using a container if found.
Habitat & Behavior
Habitat & Range
Found primarily in the Midwestern and Southern United States, extending south to the Gulf Coast and west to Texas. Prefers dry, sheltered microhabitats in dark, undisturbed places both outdoors under rocks and indoors in human dwellings.
Behavior & Temperament
Reclusive, nocturnal hunters that actively forage away from their retreat web 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
Predominantly feeds on small insects such as cockroaches, crickets, and other soft-bodied arthropods captured during nocturnal forays.
Seasonal Activity
Most active during spring, summer, and early autumn. During colder winter months, they seek shelter indoors and remain relatively dormant.
Description
The brown recluse is a well-known nocturnal dweller of dark, undisturbed corners. Recognized by its fiddle-shaped marking and unusual six-eye arrangement, it plays a vital predatory role in controlling household and outdoor insect populations.
Key Features
Presence of a dark violin-shaped marking on the dorsal cephalothorax, exactly six eyes arranged in three pairs (dyads), uniformly colored legs without bands, and a uniform tan-to-brown abdomen.
Similar Species
Cellar spiders (Pholcidae), male funnel-web grass spiders, and various wolf spiders are often mistaken for brown recluses, but can be distinguished by eye count, body markings, and leg spination.
Life Cycle
Females produce several silk egg sacs containing around 30 to 50 eggs during the warmer months. Spiderlings emerge and undergo multiple molts over a lifespan that can reach 1 to 2 years.
Ecological Importance
Functions as an effective predator of household and agricultural insect pests, helping regulate arthropod populations within its geographic range.
Conservation Status
Not evaluated by the IUCN, but populations are secure and widespread within their native geographic range.
Interesting Facts
Brown recluses can survive for months without food or water, and their venom contains specialized enzymes evolved specifically to rapidly digest prey tissues from the inside out.
Photography Tips
Photograph from a safe distance using macro lenses with good lighting. Focus clearly on the dorsal carapace to capture the violin marking and the eye region to show the six-eye arrangement.
Identified: 2026-08-23T00:27:38.591832