Hobo Spider, Field Spider
Eratigena agrestis
Agelenidae (Funnel Weavers), Order Araneae
Physical Description
The Hobo Spider features a distinctively elongated, oval-shaped abdomen and a clearly defined, elongated cephalothorax. The body texture is finely covered in short, microscopic hairs, giving it a somewhat matte appearance rather than a glossy shine. It lacks the prominent dark chevron markings on the sternum found in some related species, but exhibits a subtle patterned design on the dorsal abdomen.
Size Estimate
Body length typically ranges from 11 to 18 millimeters for females and 8 to 14 millimeters for males. The leg span can reach up to 40 to 50 millimeters, making it a moderately large house-dwelling spider.
Coloration & Markings
Predominantly brown in various shades, ranging from light yellowish-brown to dark brown. The dorsal abdomen features a distinct pattern of yellowish or pale brown herringbone or chevron markings pointing forward. The cephalothorax is typically a uniform light brown with faint darker radial stripes, and the legs are generally a solid, uniform brown without distinct dark banding.
Web Type
Builds a characteristic funnel-shaped sheet web. The web consists of a flat, densely woven sheet of silk that extends out from a tubular retreat where the spider hides, waiting for prey to walk across the sheet.
Eye Arrangement
Has eight small eyes of roughly equal size, arranged in two horizontal rows of four eyes each across the front of the cephalothorax. The rows are slightly curved, which is typical for the family Agelenidae.
Leg Characteristics
Legs are long, moderately stout, and covered in fine hairs and visible spines. They lack distinct dark rings or bands, giving them a uniform brownish appearance. The legs are often held spread out flat against the surface in a sprawling posture.
Venom & Safety Information
Venom Information
Possesses a proteinaceous venom containing necrotic components. While historical controversy surrounded its medical impact, bites can cause localized pain, redness, and in some cases, slow-healing necrotic lesions similar to a mild brown recluse bite.
Medical Significance
Considered medically significant in regions where it has been introduced. Bites can result in localized tissue damage, severe headaches, and hard-to-heal wounds. Medical attention should be sought if a bite causes expanding redness, blistering, or systemic symptoms.
Safety Recommendations
Wear gloves when moving woodpiles or working in dark crawlspaces. Keep beds away from walls and avoid leaving clothing on the floor. If found inside, relocate safely using a cup and a piece of cardboard rather than handling directly.
Habitat & Behavior
Habitat & Range
Native to Europe and Central Asia, the Hobo Spider has been introduced to the Pacific Northwest of the United States and parts of western Canada. It prefers dark, moist, and undisturbed areas such as tall grass, woodpiles, rock walls, and inside human dwellings near baseboards or under furniture.
Behavior & Temperament
Primarily nocturnal and a defensive rather than aggressive spider. It relies heavily on its speed to escape threats, but will bite if cornered, trapped against the skin, or when defending its egg sac.
Diet & Prey
Feeds primarily on crawling insects such as beetles, roaches, earwigs, flies, and other spiders. It intercepts prey running across its sheet web and subdues them with venom before dragging them into its funnel retreat.
Seasonal Activity
Most commonly encountered in late summer and autumn (August through October) when mature males actively wander in search of females during the mating season.
Description
The Hobo Spider is a fast-running funnel weaver commonly associated with human habitations and outbuildings. Recognizable by its uniform brown coloration and distinctive herringbone pattern on the abdomen, this spider constructs tangled funnel webs near ground level. While reclusive and quick to flee, it commands respect due to the potential medical significance of its bite.
Key Features
Uniformly brown legs without banding, a clear herringbone or chevron pattern on the dorsal abdomen, construction of a funnel-shaped sheet web, and a lack of dark markings on the sternum.
Similar Species
Giant House Spider (Eratigena duress) and Domestic House Spider (Tegenaria domestica). These can be distinguished by subtle genital morphology, leg banding patterns, and slight variations in the sternum markings.
Life Cycle
Females construct tough, disc-shaped silk egg sacs in the autumn, depositing dozens to hundreds of eggs inside. Spiderlings hatch the following spring, undergo multiple molts to reach maturity by late summer, and typically live for one to two years.
Ecological Importance
Serves as an effective predator of household and agricultural insect pests, helping to naturally regulate populations of crawling bugs and other arthropods within its habitat.
Conservation Status
Not evaluated by the IUCN. It is a secure, widespread species and is considered an invasive or introduced pest in parts of North America.
Interesting Facts
Despite its common name 'hobo,' the name actually derives from the species name 'agrestis,' which means 'rural' or 'field.' They are surprisingly fast runners, capable of reaching speeds that make them seem deceptively agile.
Photography Tips
Use a macro lens with a fast shutter speed to capture details of the abdominal chevron pattern and eye arrangement. Ensure good lighting without harsh shadows, and maintain a safe distance to avoid startling the spider.
Identified: 2026-10-16T14:48:33.272770