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 distinct pairs, and a venom apparatus containing potent sphingomyelinase D.
Physical Description
The brown recluse has a uniform light brown to dark brown body with a distinctly violin-shaped marking on its cephalothorax, pointing toward the rear. The abdomen is oval, covered in fine, short hairs, and lacks distinct patterns or stripes.
Size Estimate
Body length typically ranges from 6 to 20 mm (about 1/4 to 3/4 inch), with a leg span of approximately 25 to 50 mm (1 to 2 inches). The specimen shown is an adult of moderate size.
Coloration & Markings
Coloration ranges from yellowish-brown to dark brown. The hallmark marking is the dark violin shape on the dorsal carapace, with the neck of the violin pointing backward. The abdomen is typically a solid, uniform grayish-brown.
Web Type
Builds irregular, loose, sticky webs used primarily as daytime retreat shelters rather than for active prey capture. These webs are typically found in dark, undisturbed areas close to the ground.
Eye Arrangement
Uniquely possesses only six eyes arranged in three dyads (pairs): one pair in front and a pair on each side, leaving a characteristic gap between the pairs. This differs from most spiders which have eight eyes.
Leg Characteristics
Long, thin, and spindly legs lacking prominent spines or distinct banding. The legs are uniformly colored and held in a spread posture when resting or startled.
Venom & Safety Information
Venom Information
Contains a potent necrotic venom primarily composed of the enzyme sphingomyelinase D, which destroys cell membranes and causes localized tissue breakdown.
Medical Significance
Medically significant. Bites can result in dermonecrotic lesions, slow-healing wounds, and in rare cases systemic symptoms (loxoscelism). Immediate medical attention is recommended if a bite is suspected.
Safety Recommendations
Shake out shoes and clothing left on the floor, wear gloves when moving stored items in dark areas, and safely relocate or eliminate individuals using a jar and piece of cardboard.
Habitat & Behavior
Habitat & Range
Native to the central and southern United States, ranging from the Midwest down to Texas and eastward to Georgia. Prefers dry, sheltered microhabitats such as woodpiles, basements, attics, closets, and behind furniture.
Behavior & Temperament
Timid and non-aggressive, actively fleeing from disturbance. They are nocturnal hunters that forage away from their retreat webs at night.
Diet & Prey
Feeds primarily on small insects such as cockroaches, crickets, and silverfish, subduing them with potent venom after a brief struggle.
Seasonal Activity
Most active during warmer spring and summer months, though indoor specimens remain active year-round due to climate-controlled environments.
Description
The brown recluse is a famously misunderstood synanthropic spider known for its violin-shaped marking and medically significant necrotic venom. While reclusive and rarely biting unless trapped against human skin, encounters in homes require cautious handling.
Key Features
Six eyes arranged in three pairs, uniform brown legs without spines or bands, and the distinctive dark violin shape on the cephalothorax.
Similar Species
Cellar spiders (Pholcidae), funnel-web grass spiders (Agelenidae), and other harmless relict or cellar-dwelling spiders. They can be distinguished by counting the eyes and checking for the violin pattern.
Life Cycle
Females produce several spherical, off-white egg sacs containing up to 50 eggs each during the summer months. Spiderlings molt multiple times before reaching maturity, with a potential lifespan of 1 to 3 years.
Ecological Importance
Serves as an effective predator of household insect pests, helping to regulate populations of cockroaches and other unwanted invertebrates.
Conservation Status
Not evaluated by the IUCN, but highly abundant and secure throughout its native geographic range.
Interesting Facts
Brown recluses can survive for months without food or water in extremely dry indoor environments, making them well-adapted to human structures.
Photography Tips
Photograph from a safe distance using macro lenses and natural side lighting to highlight the cephalothorax markings and eye arrangement without provoking the spider.
Identified: 2026-08-30T15:41:42.682509