Hobo Spider, Aggressive House Spider
Eratigena agrestis
Agelenidae (Funnel Web Weavers), Order Araneae. Key family characteristics include three pairs of spinnerets with the posterior pair being noticeably elongated, and a distinctive sheet-like web that ends in a funnel-shaped retreat.
Physical Description
Robust body with a brown cephalothorax featuring darker longitudinal stripes, and a mottled, brownish-grey abdomen displaying a distinct chevron or herringbone pattern down the dorsal midline. Texture appears somewhat smooth with fine hairs.
Size Estimate
Body length typically ranges from 11 to 18 mm for females and 9 to 15 mm for males, with a total leg span reaching up to 40 mm. This specimen appears to be a subadult or adult.
Coloration & Markings
Muted brown, tan, and grey tones. The defining feature is the pattern of yellowish-brown or grey chevrons on the dorsal abdomen pointing forward. Unlike some spiders, it lacks conspicuous banding on the legs, which are typically a uniform light brown.
Web Type
Asymmetric sheet web made of dense, non-sticky silk that spans across ground-level crevices, logs, or foundations, terminating in a tubular retreat where the spider lies in wait.
Eye Arrangement
Eight eyes arranged in two slightly curved, nearly parallel horizontal rows of four, typical of funnel-weaving spiders.
Leg Characteristics
Long, moderately thick legs covered in fine hairs and visible spines, lacking distinct dark banding. They are held in a sprawling posture, adapted for rapid running across the sheet web.
Venom & Safety Information
Venom Information
Contains neurotoxic and necrotic components, historically suspected of causing necrotic lesions, though modern toxicology suggests effects are typically mild localized pain and redness unless complicated by secondary infection.
Medical Significance
Historically considered medically significant due to fears of necrotic bites, but current consensus leans toward mild to moderate local reactions similar to a bee sting, with rare severe dermonecrotic cases.
Safety Recommendations
Wear gloves when moving woodpiles or clearing debris, seal foundation cracks to prevent indoor entry, and safely relocate stray spiders using a container and a piece of stiff paper.
Habitat & Behavior
Habitat & Range
Native to Europe and introduced to the Pacific Northwest of North America and parts of Central Asia. Found in moist, dark crevices, under logs, rocks, and occasionally in basements or window wells around human structures.
Behavior & Temperament
Fast-moving, ground-dwelling ambush predator. Generally defensive rather than aggressive, biting only when firmly trapped or accidentally squeezed against human skin.
Diet & Prey
Insects and other small arthropods that blunder onto the horizontal sheet web, which the spider subdues with a rapid rush from the funnel retreat.
Seasonal Activity
Most active during late summer and autumn when mature males wander extensively in search of females during the mating season.
Description
The hobo spider is a robust brown funnel-weaver often encountered near the ground in damp outdoor microhabitats or occasionally making its way indoors. Recognized by its distinct abdominal chevron pattern and non-sticky sheet web, it is a master runner rather than a web-spinner of sticky traps.
Key Features
Distinctive herringbone or chevron pattern on the dorsal abdomen, uniform brown unbanded legs, and construction of a funnel-shaped retreat on a sheet web.
Similar Species
Giant House Spider (Eratigena duatrica) and Barn Funnel Weaver (Tegenaria domestica). Distinguished primarily by subtle genital morphology, size differences, and the exact clarity of the abdominal chevron pattern.
Life Cycle
Females construct tough, disc-shaped silken egg sacs in the autumn, depositing dozens of eggs that overwinter and hatch in spring. Spiderlings mature over one to two years through multiple molts.
Ecological Importance
Serves as an effective predator of ground-dwelling insects, playing a role in regulating pest populations in gardens and natural woodland floors.
Conservation Status
Not threatened; secure and widespread across its native and introduced ranges, sometimes considered a nuisance pest when entering homes.
Interesting Facts
Despite its specific epithet 'agrestis' meaning 'rural' or 'field', it has successfully colonized urban and suburban habitats, and its common name 'hobo' stems from the belief that it traveled along railroad tracks.
Photography Tips
Photograph from a dorsal angle to clearly capture the chevron pattern on the abdomen and the lack of leg banding. Use natural lighting or diffused flash to avoid harsh reflections.
User Notes
Found on a funnel web on a log
Identified: 2026-09-19T19:56:29.222819