Hobo Spider, Aggressive House Spider
Eratigena agrestis
Agelenidae (Funnel Web Weavers), Order Araneae. Key family characteristics include long spinnerets and a distinctive funnel-shaped retreat in their webs.
Physical Description
Robust body with a brown-to-grey cephalothorax featuring distinct darker brown longitudinal stripes. The abdomen is mottled grey-brown with a pattern of yellowish, chevron-shaped markings pointing forward. The texture is covered in fine setae rather than smooth or spiny.
Size Estimate
Body length ranges from 11 to 18 mm for females and 9 to 15 mm for males. Leg span can reach up to 40 to 45 mm. This specimen appears to be a mature adult.
Coloration & Markings
Dull brown base coloration with distinct V-shaped or chevron markings down the dorsal side of the abdomen. The sternum typically lacks distinct light markings, and the legs are uniformly brownish without clear banding.
Web Type
Builds a non-sticky, sheet-like funnel web close to the ground, foundation walls, or under objects in dark, undisturbed areas. The sheet extends into a tubular retreat where the spider waits.
Eye Arrangement
Eight eyes of roughly equal size arranged in two slightly curved, nearly parallel horizontal rows.
Leg Characteristics
Long, relatively robust legs covered in fine hairs and visible spines. The legs are uniform in color without prominent rings or dark bands, and they spread out flat against surfaces when resting.
Venom & Safety Information
Venom Information
Cytotoxic venom. Historically feared as capable of causing necrotic lesions, though modern medical research suggests many attributed necrosis cases were secondary bacterial infections or due to other factors.
Medical Significance
Historically classified as a medically significant spider with bites causing localized pain, redness, and sometimes slow-healing wounds. Contemporary consensus suggests bites are mild to moderate, but medical attention is recommended if symptoms worsen or a necrotic lesion begins to develop.
Safety Recommendations
Wear gloves when moving firewood or cleaning out dark, undisturbed storage areas. If found indoors, safely capture it using a container and piece of paper to release it outside.
Habitat & Behavior
Habitat & Range
Native to Europe and Central Asia; introduced to the Pacific Northwest of North America. Prefers dry, dark cavities, rock piles, woodpiles, and near the ground around human habitations.
Behavior & Temperament
Crepuscular to nocturnal hunter that stays primarily within its funnel retreat unless disturbed or seeking a mate. Not inherently aggressive, but will bite if trapped against human skin or roughly handled.
Diet & Prey
Generalist predator feeding primarily on crawling ground insects such as beetles, earwigs, cockroaches, and other spiders that stumble onto the non-sticky sheet web.
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 medium-sized funnel weaver known for constructing dense sheet webs near ground level. While once widely feared due to suspected necrotic venom effects, they are typically reclusive and avoid human contact unless cornered. Their mottled grey-brown coloration and chevron patterns help them blend seamlessly into woodpiles and crevices.
Key Features
Uniformly colored legs without bands, distinctive chevron patterns on the abdomen, lack of distinct markings on the sternum, and construction of a low-lying funnel web.
Similar Species
Giant House Spider (Eratigena atrica), Domestic House Spider (Tegenaria domestica), and Wolf Spiders (Lycosidae). Distinguished by examining leg banding, sternum patterns, and microscopic genital structures.
Life Cycle
Females lay disc-shaped egg sacs in the autumn, covering them with silk and debris near the web. Spiderlings hatch in spring, undergo multiple molts, and reach maturity by late summer. Lifespan is typically 1 to 2 years.
Ecological Importance
Acts as an effective natural population controller for ground-dwelling insects and agricultural pests around homes and gardens.
Conservation Status
Not evaluated by the IUCN, but abundant and widespread throughout its native and introduced ranges.
Interesting Facts
Despite the species name 'agrestis' meaning 'rural' or 'field', they frequently end up in human structures. They are remarkably poor climbers on smooth vertical surfaces like glass or porcelain.
Photography Tips
Photograph from a safe distance using macro lenses in natural, diffused light. Capture dorsal views of the abdomen patterns and a clear view of the legs to highlight the absence of banding.
Identified: 2026-08-23T00:38:31.164653