Hobo Spider, Aggressive House Spider
Eratigena agrestis
Agelenidae (Funnel-Weavers), Order Araneae
Physical Description
Robust, elongated body with a distinct fiddle or chevron pattern on the carapace, though less defined than in recluses. The abdomen is grayish-brown with distinctive yellowish-brown herringbone patterns. It has a slightly hairy texture and prominent palps.
Size Estimate
Body length ranges from 11 to 18 mm for females and 9 to 15 mm for males, with a leg span reaching up to 40 to 50 mm. This specimen appears to be a mature adult.
Coloration & Markings
Muted brownish-gray base coloration with pale yellowish markings. The dorsal abdomen features a distinct chevron or herringbone pattern pointing forward, while the sternum has a pale yellowish stripe down the middle.
Web Type
Constructs a dense, non-sticky sheet web that funnels into a tubular retreat where the spider waits for prey, typically built in dark, low corners.
Eye Arrangement
Eight small, dark eyes arranged in two slightly curved, nearly parallel horizontal rows of four, typical of funnel-weaver spiders.
Leg Characteristics
Long, robust legs covered in fine hairs and visible spines. The legs lack distinct dark banding, presenting a uniform brownish or greyish color, and are often held in a flattened, sprawling posture.
Venom & Safety Information
Venom Information
Contains a cytotoxic venom. While historical reports associated its bite with necrotic lesions (similar to a recluse), modern toxicology suggests bites result in localized pain, redness, and headaches rather than severe tissue necrosis.
Medical Significance
Historically considered dangerous due to suspected necrotic bites, but current medical consensus views its venom as significantly less dangerous than once feared. Bites are uncommon and typically result in temporary localized symptoms requiring standard first aid.
Safety Recommendations
Wear gloves when clearing dark, undisturbed areas like woodpiles or basements. If found indoors, gently guide the spider into a container using a piece of cardstock and release it outdoors.
Habitat & Behavior
Habitat & Range
Originally native to Europe and Central Asia, introduced to the Pacific Northwest of North America and parts of Western Canada. Found in dark, moist areas, under rocks, in woodpiles, or low to the ground in homes and outbuildings.
Behavior & Temperament
Typically defensive rather than aggressive, biting mostly when trapped against human skin or squeezed. They have poor eyesight and rely heavily on vibrations transmitted through their webs.
Diet & Prey
Carnivorous, feeding primarily on crawling insects such as beetles, flies, cockroaches, and earwigs trapped on or near its funnel web.
Seasonal Activity
Most active during late summer and autumn, particularly from August to October, when mature males actively wander in search of females.
Description
The Hobo Spider is a classic funnel-weaver known for building dense, sheet-like webs close to the ground. While its common and scientific names once falsely branded it as aggressively dangerous, it is generally reclusive and avoids human contact unless provoked.
Key Features
Distinguished by the lack of dark banding on the legs, a distinct herringbone pattern on the abdomen, and a funnel-shaped retreat rather than an orb or tangle web.
Similar Species
Often confused with the Brown Recluse (Loxosceles reclusa) and Giant House Spider (Eratigena atrica). Distinguished from the brown recluse by the absence of a violin-shaped mark on the cephalothorax and the presence of patterned markings on the abdomen.
Life Cycle
Females produce flat, disc-shaped silk egg sacs containing around 50 to 100 eggs in the fall, which overwinter and hatch in spring. Mating occurs in late summer and autumn, after which many mature males die off.
Ecological Importance
Serves as an effective natural predator for various crawling household and garden pests, helping to naturally regulate insect populations.
Conservation Status
Not evaluated by the IUCN, but secure and locally abundant throughout its native and introduced ranges.
Interesting Facts
Despite the species name 'agrestis' meaning 'rural' or 'field' in Latin, in North America it is predominantly found in urban and domestic environments around human habitations.
Photography Tips
Photograph from a safe distance using macro lenses in natural lighting. Capture dorsal views to clearly show the abdominal herringbone pattern and the leg structures for accurate identification.
Identified: 2026-08-09T06:30:50.977053