Hobo Spider, Field Funnel-Weaver
Eratigena agrestis
Agelenidae (Funnel Weavers), Order Araneae. Key family characteristics include long spinnerets extending past the rear of the abdomen and a tendency to build sheet webs terminating in a tubular retreat.
Physical Description
Robust body structure with a distinctively patterned dorsal surface, elongated abdomen, and prominent spiny legs. The cephalothorax is longer than it is wide, and the body is covered in fine setae.
Size Estimate
Body length ranges from 11 to 18 mm for females and 9 to 15 mm for males, with a total leg span reaching up to 40 to 45 mm. This specimen appears to be an adult.
Coloration & Markings
Muted brown coloration featuring a distinct, chevron-like pattern (herringbone pattern) along the dorsal midline of the abdomen. The cephalothorax typically has indistinct yellowish-brown longitudinal stripes.
Web Type
Constructs a dense, non-sticky horizontal sheet web that ends in a funnel-shaped retreat where the spider waits for prey to trigger the silk trip-lines.
Eye Arrangement
Eight eyes of roughly equal size arranged in two nearly straight or slightly curved horizontal rows across the front of the cephalothorax.
Leg Characteristics
Long, robust legs covered in noticeable spines and hairs. The legs lack distinct dark banding, which helps distinguish it from some similar species, and are held flat against surfaces when resting.
Venom & Safety Information
Venom Information
Contains a cytotoxic venom that can cause localized tissue necrosis in rare instances, though most bites result in localized pain, redness, and swelling similar to a bee sting.
Medical Significance
Historically considered medically significant due to suspected necrotic bite reports, though modern toxicology suggests their danger has been exaggerated and systemic effects are rare.
Safety Recommendations
Wear gloves when moving firewood or cleaning out dark crawlspaces. If found indoors, gently guide it into a container using a piece of cardstock and release it outdoors.
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 rocks, in woodpiles, and frequently around human foundations and crawlspaces.
Behavior & Temperament
Aggressive only when cornered or trapped against the skin. They are primarily nocturnal hunters, spending daylight hours inside their funnel retreats.
Diet & Prey
Generalist predator feeding primarily on crawling insects such as beetles, roaches, earwigs, and flies, which become trapped on the horizontal sheet web.
Seasonal Activity
Most active during late summer and autumn (August to October), which is when mature males actively wander in search of mates, leading to increased human encounters.
Description
The Hobo Spider is a quintessential funnel-weaver, known for its distinct sheet webs built near the ground in dark, undisturbed areas. While often feared due to historical misconceptions regarding its venom, it is a shy creature that prefers to flee rather than fight.
Key Features
Absence of dark banding on the legs, distinctive herringbone pattern on the dorsal abdomen, and the construction of a funnel-shaped retreat web.
Similar Species
Giant House Spider (Eratigena atrica) and Domestic House Spider (Tegenaria domestica). Distinguished primarily by subtle genital differences and slightly different abdominal marking clarity.
Life Cycle
Females lay eggs in silk egg sacs hidden within the retreat during late summer. Spiderlings emerge the following spring, undergoing multiple molts to reach maturity by late summer.
Ecological Importance
Acts as an effective natural pest control agent by reducing populations of crawling insects and agricultural pests around homes and gardens.
Conservation Status
Not evaluated by the IUCN, but populations are stable and thriving across its native and introduced ranges.
Interesting Facts
Despite the common name 'hobo,' the name actually derives from the species name agrestis, meaning 'rural' or 'of the fields,' though it has successfully adapted to urban environments.
Photography Tips
Use a macro lens with a ring flash or external diffuser to capture the detailed herringbone pattern on the abdomen and the spination on the legs while maintaining a safe distance.
Identified: 2026-09-05T20:06:16.686760