Brown Recluse Spider, Fiddle-back Spider, Violin Spider
Loxosceles reclusa (or similar Loxosceles species)
Sicariidae (Six-eyed Sicariid Spiders), Order Araneae. Key family characteristics include having only six eyes arranged in three dyads and necrotic venom.
Physical Description
The spider has a somewhat flattened body with distinct cephalothorax and oval abdomen. The surface is covered in fine, short hairs rather than heavy spines. Sexual dimorphism is minimal, though males often have slightly more slender abdomens and longer legs.
Size Estimate
Body length typically ranges from 6 to 20 millimeters (about 0.25 to 0.75 inches), with a leg span reaching up to 25 to 30 millimeters (1 inch). The specimen in the image appears to be within the typical adult range.
Coloration & Markings
Coloration ranges from light tan to dark brown. The most diagnostic marking is the darker violin-shaped pattern on the dorsal carapace, with the neck of the violin pointing backward toward the abdomen.
Web Type
Builds irregular, disorganized, sticky retreat webs rather than symmetrical orb webs. These webs are typically constructed in dark, undisturbed areas such as woodpiles, basements, closets, and behind furniture.
Eye Arrangement
Uniquely features only six eyes arranged in three pairs (dyads): one median pair and two lateral pairs. This differs from the standard eight eyes found in most spider families.
Leg Characteristics
Legs are long, slender, and uniformly colored without prominent bands, stripes, or heavy spination. They are typically spread out flat against surfaces when the spider is at rest.
Venom & Safety Information
Venom Information
Contains a potent cytotoxic and hemolytic venom containing the enzyme sphingomyelinase D, which can cause local tissue destruction, necrosis, and systemic reactions in rare cases.
Medical Significance
Medically significant. Bites can result in necrotic skin lesions (dermonecrotic arachnidism) that heal slowly and may require medical intervention. Most bites are minor, but prompt medical attention is advised if skin ulceration develops.
Safety Recommendations
Shake out shoes and clothing left on the floor, wear gloves when moving stored items in dark areas, seal entry points to homes, and gently relocate individuals outdoors using a container and a piece of paper.
Habitat & Behavior
Habitat & Range
Found primarily in the central and southern United States, extending from midwestern states down to the Gulf Coast. Prefers dry, sheltered, undisturbed microhabitats both outdoors (under rocks, bark) and indoors (attics, basements, closets).
Behavior & Temperament
Reclusive, nocturnal hunters that actively forage for prey rather than waiting in a web. 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
Feeds primarily on small insects such as cockroaches, crickets, and other soft-bodied arthropods, using stealth and active hunting techniques.
Seasonal Activity
Most active during spring, summer, and early autumn. In cooler months, they seek shelter indoors and remain relatively dormant unless disturbed in heated structures.
Description
The brown recluse is a shy, nocturnal inhabitant of dark corners and crevices, famously recognized by the violin-shaped marking on its cephalothorax. While capable of delivering a medically significant necrotic bite, it is fundamentally non-aggressive and prefers to flee rather than fight.
Key Features
Distinctive violin-shaped marking on the cephalothorax, six eyes arranged in three pairs, uniform brown legs without banding, and lack of strong spines.
Similar Species
Cellar spiders (Pholcidae), grass spiders (Agelenidae), and male southern house spiders (Kukulcania hibernalis) are often mistaken for brown recluses due to color or shape, but they possess eight eyes, different markings, or hairy legs.
Life Cycle
Females produce several white silk egg sacs containing around 30 to 50 eggs each during the warmer months. Spiderlings undergo multiple molts over a lifespan that can extend up to 1 to 3 years.
Ecological Importance
Acts as an effective natural predator of household and garden insect pests, helping to control populations of roaches, crickets, and other invertebrates.
Conservation Status
Not evaluated by the IUCN, but populations are generally stable and abundant throughout their native range.
Interesting Facts
Brown recluses can survive for months without food or water, and their venom contains enzymes specifically evolved to break down mammalian tissue for easier digestion.
Photography Tips
Use macro lenses with adequate, diffused lighting to capture the dorsal pattern and eye arrangement clearly. Maintain a safe distance and avoid provoking the spider.
Identified: 2026-08-18T16:11:48.342950