Brown Recluse Spider, Fiddleback Spider, Violin Spider
Loxosceles reclusa (or closely related Loxosceles species)
Sicariidae (Six-eyed Sicariid Spiders), Order Araneae. Key family characteristics include having only six eyes arranged in three dyads and a tendency to inhabit dry, dark, undisturbed places.
Physical Description
The spider has a distinctively uniform, matte appearance with long, thin legs and no prominent spines. The cephalothorax features a characteristic darker violin-shaped marking with the neck pointing toward the abdomen. The abdomen is oval, covered in fine, short hairs, and typically lacks complex patterned markings.
Size Estimate
Body length ranges from 6 to 20 mm (approximately 1/4 to 3/4 inch), with a leg span that can reach up to 25 to 30 mm (around 1 inch). The specimen in the image appears small, possibly a late-stage juvenile or an adult male.
Coloration & Markings
Coloration ranges from light tan to dark brown. The defining marking is the dark violin-shaped pattern on the dorsal carapace. The abdomen is uniformly colored, usually grayish-brown, beige, or dark yellow, without stripes or colorful bands.
Web Type
Irregular cobweb or tangle web constructed in dark, sheltered retreats. The web is not used to actively snare flying prey with sticky spirals, but rather serves as a daytime retreat and sensory platform with trip lines.
Eye Arrangement
Unusual arrangement of six eyes in total, grouped into three distinct pairs (dyads): one median pair and two lateral pairs. This contrasts with the typical eight-eyed pattern of most true spiders.
Leg Characteristics
Legs are long, slender, and uniformly colored without visible banding, spines, or prominent hairs. When resting, the spider often holds its legs outstretched or flat against a surface in a defensive or ambush posture.
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 mild skin irritation or go unnoticed, some can cause severe localized necrotic ulcers (loxoscelism) that require medical attention. Systemic reactions are rare but possible.
Safety Recommendations
Inspect and shake out clothing or shoes left on the floor. Avoid reaching blindly under furniture, into dark closets, or behind stored boxes. Use gloves when moving firewood or stored items, and safely relocate spiders using a jar and stiff paper if found indoors.
Habitat & Behavior
Habitat & Range
Found primarily in the central and southern United States, extending into parts of the Midwest. Prefers dry, dark, undisturbed microhabitats such as woodpiles, basements, closets, attics, and underneath furniture (as indicated by the context).
Behavior & Temperament
Reclusive, nocturnal hunters. They are non-aggressive and typically bite only when trapped against the skin (such as inside clothing, shoes, or under furniture). They flee rapidly when disturbed.
Diet & Prey
Primarily feeds on small insects such as cockroaches, crickets, and silverfish. They actively hunt near their retreat or ambush prey that wanders into their irregular web.
Seasonal Activity
Most active during spring, summer, and fall. During winter, they typically seek shelter indoors and remain relatively dormant unless exposed to warm temperatures.
Description
The brown recluse is a famously misunderstood synanthropic spider known for its characteristic violin marking. While shy and retiring, its potent necrotic venom warrants caution when it shares living spaces with humans, particularly in dark, undisturbed areas beneath furniture.
Key Features
Six eyes arranged in three pairs, a distinct dark violin-shaped marking on the cephalothorax pointing backward, uniformly colored legs without bands, and a solid tan-to-brown abdomen without striking patterns.
Similar Species
Cellar spiders (Pholcidae), grass spiders (Agelenidae), and male huntsman spiders. Unlike the brown recluse, cellar spiders have very long, delicate legs and eight eyes; grass spiders feature distinct abdominal patterns and spinnerets; and other lookalikes lack the specific six-eye arrangement and violin mark.
Life Cycle
Females produce several spherical, off-white egg sacs containing around 50 eggs each during the warm months. Spiderlings molt multiple times, reaching maturity in about a year. Total lifespan can be 2 to 4 years.
Ecological Importance
Acts as an effective natural predator for household pest populations, helping to control numbers of roaches, crickets, and other unwanted insects.
Conservation Status
Not evaluated by the IUCN, but highly abundant within its native geographic range. Considered a household pest rather than a conservation concern.
Interesting Facts
Brown recluses can survive for months without food or water. Despite their fearsome reputation, they have relatively short fangs that often struggle to penetrate thick human clothing.
Photography Tips
Use macro lenses with adequate lighting to capture the diagnostic eye arrangement and the violin pattern on the carapace. Maintain a safe distance and avoid touching or provoking the spider.
User Notes
Under a chair
Identified: 2026-08-14T10:02:30.627783