Hobo Spider, Field Funnel Weaver
Eratigena agrestis
Agelenidae (Funnel Weavers), Order Araneae. Key family characteristics include three pairs of spinnerets, with the posterior spinnerets noticeably elongated, and building sheet webs that lead into a tubular retreat.
Physical Description
The spider has a relatively uniform brown body with a distinctly patterned abdomen. The cephalothorax is elongated and brownish, while the abdomen features a herringbone or chevron pattern of alternating light and dark markings. It lacks noticeable dark bands on the legs, distinguishing it from some related species.
Size Estimate
Body length is approximately 11 to 18 millimeters for females and 8 to 14 millimeters for males. The total leg span can reach up to 40 to 45 millimeters. This appears to be an adult or sub-adult specimen.
Coloration & Markings
Base coloration ranges from yellowish-brown to dark brown. The defining feature is the distinct chevron or herringbone pattern down the dorsal surface of the oblong abdomen. The legs are generally a solid, uniform brown without distinct dark banding.
Web Type
Builds a characteristic non-sticky sheet web (funnel web) that spans across crevices, low vegetation, or structural corners, terminating in a tubular retreat where the spider hides while waiting for prey.
Eye Arrangement
Eight small eyes of roughly equal size arranged in two slightly curved, nearly parallel horizontal rows across the front of the carapace.
Leg Characteristics
Long, robust legs covered in visible hairs and spines. The legs are uniformly colored brown without contrasting dark rings or bands, which is a key diagnostic feature for the species.
Venom & Safety Information
Venom Information
Possesses a necrotic venom, though historical claims of severe human tissue necrosis (necrotizing arachnidism) from bites are largely debated or attributed to secondary infections. Bites can cause localized pain, redness, and induration.
Medical Significance
Historically considered medically significant due to fears of necrotic lesions, modern toxicology and arachnology suggest their bite effects are generally mild to moderate, resembling a bee or wasp sting with localized swelling and temporary pain.
Safety Recommendations
Shake out shoes and clothing left on the floor, wear gloves when moving firewood or cleaning dark basements, and safely relocate indoor spiders outside using a cup and card.
Habitat & Behavior
Habitat & Range
Originally native to Europe and Central Asia, introduced to the Pacific Northwest of North America. Found primarily in dark, damp areas, tall grass, foundations, woodpiles, and occasionally inside houses near baseboards or basements.
Behavior & Temperament
Defensive rather than aggressive, typically fleeing when disturbed. They are primarily nocturnal hunters that rely on vibrations in their sheet webs to detect prey.
Diet & Prey
Generalist predators feeding on crawling insects such as beetles, roaches, flies, and other spiders that stumble onto their horizontal sheet webs.
Seasonal Activity
Most commonly seen in late summer and autumn (August to October), when sexually mature males actively wander in search of mates, frequently encountering humans.
Description
The Hobo Spider is a classic funnel weaver known for its speed and characteristic sheet web. Sporting a modest brown coat with a distinct chevron pattern, it is a master of structural corners and dark recesses. While once heavily feared, modern understanding paints it as a cautious resident of human dwellings and gardens, playing a quiet role in insect control.
Key Features
Uniformly brown legs without banding, a distinct chevron/herringbone pattern on the abdomen, and construction of a horizontal funnel-shaped sheet web.
Similar Species
Giant House Spider (Eratigena atrica) and Domestic House Spider (Tegenaria domestica). These can be distinguished by leg banding patterns and subtle differences in internal genitalia.
Life Cycle
Females construct tough, disc-shaped silk egg sacs in autumn, depositing dozens of eggs inside. Spiderlings emerge in spring, undergoing multiple molts to reach maturity by late summer or autumn. Adults typically live for one to two years.
Ecological Importance
Acts as an effective natural pest controller by reducing populations of crawling insects around homes, outbuildings, and agricultural fields.
Conservation Status
Not evaluated by the IUCN, but highly abundant and expanding its introduced range successfully.
Interesting Facts
The common name 'hobo' comes from the belief that they traveled along railway tracks, though they actually spread through human commerce and natural dispersal.
Photography Tips
Use macro lenses with adequate natural lighting or ring flashes to capture the abdominal chevron pattern and uniform leg coloration clearly from a safe distance.
Identified: 2026-09-23T16:09:08.105376