Hobo Spider, Aggressive House Spider
Eratigena agrestis
Agelenidae (Funnel-Weavers), Order Araneae. Key family characteristics include long spinnerets extending from the rear of the abdomen and the construction of sheet-like webs that funnel into a retreat.
Physical Description
The spider has a robust body with a pear-shaped cephalothorax and an elongated, oval abdomen. It features a moderately hairy exoskeleton without striking color contrasts, presenting a somewhat uniform, earthy appearance typical of funnel-web spiders.
Size Estimate
Body length ranges from 11 to 18 millimeters for females and 9 to 15 millimeters for males, with a total leg span reaching up to 40 to 45 millimeters. This specimen appears to be an adult.
Coloration & Markings
Base coloration ranges from brownish to grayish-brown. The cephalothorax features indistinct, lighter longitudinal striping, while the dorsal abdomen typically displays a distinctive pattern of yellowish or lighter-colored chevron or herringbone markings pointing forward.
Web Type
Constructs a dense, non-sticky sheet web that extends outward from a tubular retreat where the spider hides. These webs are typically built near the ground in dark, protected crevices.
Eye Arrangement
Equipped with eight eyes arranged in two nearly parallel, slightly curved rows of four. The eyes are relatively uniform in size, which is characteristic of the Agelenidae family.
Leg Characteristics
Long, robust legs covered in fine hairs and distinct spines. Unlike some other spiders, they generally lack prominent dark banding on the legs, maintaining a uniform light brown color, and they adopt a sprawling posture.
Venom & Safety Information
Venom Information
Possesses a necrotic venom, though its potency and significance in human envenomation have been historically debated. Modern arachnology suggests systemic symptoms from bites are less severe than once widely feared.
Medical Significance
Historically considered dangerous due to alleged necrotic wounds, current medical and arachnological consensus views its bite as mildly to moderately significant, often resulting in localized pain, redness, and occasionally a slow-healing lesion.
Safety Recommendations
Avoid walking barefoot in tall grass or dark basements, shake out shoes left outdoors, and safely relocate indoor spiders using a container and a piece of cardstock rather than handling them directly.
Habitat & Behavior
Habitat & Range
Native to Europe and introduced to the Pacific Northwest of North America. Prefers low-to-the-ground microhabitats such as tall grass, woodpiles, rock walls, and dark, undisturbed corners inside buildings.
Behavior & Temperament
Primarily nocturnal hunters that wait in their funnel retreats for prey to land on the sheet web. They are generally defensive rather than aggressive, biting only when trapped against the skin or heavily provoked.
Diet & Prey
Generalist predators feeding primarily on crawling insects such as beetles, flies, ants, and cockroaches that stumble onto their horizontal sheet webs.
Seasonal Activity
Most active during late summer and autumn, which is when mature males actively wander in search of females during the mating season.
Description
The Hobo Spider is a sturdy, brownish funnel-weaver known for building dense, horizontal sheet webs near the ground. While often feared due to sensationalized historical reports regarding its venom, it is a reclusive house and garden dweller that prefers to flee rather than fight.
Key Features
Distinct herringbone pattern on the dorsal abdomen, lack of strong banding on the legs, long prominent spinnerets, and the construction of a funnel-shaped retreat leading from a flat sheet web.
Similar Species
Often confused with harmless Giant House Spiders (Eratigena duaticea) and Wolf Spiders (Lycosidae). Wolf spiders can be distinguished by their active hunting habits without webs and distinct eye arrangements, while giant house spiders are generally larger and darker.
Life Cycle
Females produce disc-shaped egg sacs in the autumn, attaching them to sheltered surfaces. Spiderlings hatch in the spring, undergo multiple molts to reach maturity, and typically have a lifespan of one to two years.
Ecological Importance
Serves as an effective natural pest control agent by reducing populations of crawling household and garden insects, while also acting as a food source for larger predators like birds and small mammals.
Conservation Status
Not evaluated by the IUCN, but populations are stable and thriving, particularly as an introduced species in North America.
Interesting Facts
Despite its specific epithet 'agrestis' meaning 'rural' or 'field' in Latin, this species frequently makes its home in close proximity to human habitations, particularly in basements and crawlspaces.
Photography Tips
Photograph from the side or slightly above to capture the distinct chevron markings on the abdomen and the leg proportions. Use natural indirect lighting or a diffused flash to avoid harsh shadows and glare on the container.
Identified: 2026-08-23T00:37:15.066620