Hobo Spider, Aggressive House Spider
Tegenaria agrestis
Agelenidae (Funnel-weave spiders), Order Araneae
Physical Description
Medium-sized spider with a relatively elongated, brownish body. The cephalothorax features characteristic darker lengthwise stripes, and the abdomen displays a distinctive pattern of chevron-shaped markings with the points facing forward.
Size Estimate
Body length ranges from 11 to 14 mm for females and 8 to 11 mm for males, with a leg span reaching up to 40 mm.
Coloration & Markings
Dull brownish coloration overall. The cephalothorax is light brown with distinct darker brown longitudinal stripes. The abdomen is mottled gray-brown featuring a series of dark chevron or herringbone patterns along the dorsal midline.
Web Type
Builds a characteristic flat, sheet-like funnel web that leads into a tubular retreat where the spider waits for prey, typically constructed in dark, protected corners near ground level.
Eye Arrangement
Eight small eyes of uniform size arranged in two slightly curved, parallel horizontal rows of four across the front of the carapace.
Leg Characteristics
Long, robust legs of uniform brown color without distinct dark banding or rings, covered in fine setae and hairs, specialized for rapid running across their sheet webs and ground.
Venom & Safety Information
Venom Information
Possesses a necrotic venom containing proteins that can cause localized tissue breakdown, though historically its reputation for severe dermonecrosis has been debated and often confused with other medical conditions.
Medical Significance
Historically considered medically significant due to fears of necrotic bites, though modern toxicology suggests localized redness, pain, and occasional slow-healing hard lesions are the typical symptoms. Seek medical attention if a bite shows signs of spreading infection or skin ulceration.
Safety Recommendations
Reduce clutter in basements and garages, seal cracks around foundations, wear gloves when moving stored items, and safely relocate specimens outdoors using a container and a piece of card.
Habitat & Behavior
Habitat & Range
Native to Europe and introduced to the Pacific Northwest of North America. Prefers dark, moist, secluded areas outdoors under rocks or logs, and indoors in basements, crawlspaces, and corners.
Behavior & Temperament
Fast-running and agile nocturnal hunters. They are generally defensive rather than aggressive, typically attempting to flee when disturbed, but will bite if trapped against skin.
Diet & Prey
Generalist predators feeding on crawling insects such as beetles, flies, roaches, and other spiders that stumble onto their sheet webs.
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 skilled web-builder often found inhabiting dark corners of human structures within its introduced range. Recognized by its distinctive herringbone abdominal pattern and lack of banded legs, it plays an effective role in controlling indoor and outdoor insect populations while preferring to keep a low profile.
Key Features
Distinct chevron or herringbone pattern on the abdomen, lack of dark banding on the legs, and the construction of a flat funnel-shaped web.
Similar Species
Giant House Spider (Eratigena atrica) which is larger and darker, and the Domestic House Spider (Tegenaria domestica), which usually displays distinct banding on the legs and palps.
Life Cycle
Females produce disc-shaped egg sacs in autumn, attaching them to sheltered surfaces. Spiderlings hatch in spring, undergo multiple molts, and reach adulthood by late summer when mating occurs. Adults typically live for one to two years.
Ecological Importance
Acts as an effective natural predator for regulating local insect populations, helping control household and garden pests.
Conservation Status
Not evaluated by the IUCN, but populations are secure and expanding in introduced regions.
Interesting Facts
Despite its specific scientific epithet 'agrestis' meaning 'rural' or 'of the fields', it has successfully adapted to urban and suburban environments, frequently coexisting in human dwellings.
Photography Tips
Use macro lenses with natural side-lighting or diffused flash to highlight the diagnostic herringbone abdominal pattern and carapace stripes without startling the spider.
Identified: 2026-10-15T03:59:14.470187