Giant House Spider
Eratigena duellica (previously Tegenaria gigantea)
Agelenidae (Funnel-Web Spiders), Order Araneae
Physical Description
A large spider with a pear-shaped cephalothorax and an elongated oval abdomen. It has a hairy appearance and prominent spinnerets at the rear of the abdomen. Large males have noticeably long legs and prominent pedipalps.
Size Estimate
Body length 10-18mm for females; leg span can reach up to 75-100mm (3-4 inches) in adult males.
Coloration & Markings
Generally earth-toned with shades of brown, grey, and tan. The cephalothorax features two dark longitudinal stripes. The abdomen has a central pale mark followed by 6 darker 'chevron' or spots against a mottled background.
Web Type
Messy, horizontal sheet-like funnel web with a tubular retreat. Often built in corners, undisturbed wall voids, or behind furniture.
Eye Arrangement
Eight eyes of similar size arranged in two slightly curved rows of four. This provides good motion detection at close range.
Leg Characteristics
Long, hairy legs without distinct banding (unlike the Hobo Spider). The legs are relatively thin compared to the body, and the first pair of legs in males is particularly elongated.
Venom & Safety Information
Venom Information
Contains neurotoxic components effective against insects but typically considered low-potency and harmless to humans.
Medical Significance
Not medically significant. Bites are rare and usually only occur if the spider is pinned against skin. Symptoms are typically limited to mild localized pain and swelling similar to a bee sting.
Safety Recommendations
Relocate using a cup and card if found indoors. Seal cracks and crevices to prevent entry. Do not handle with bare hands to avoid a defensive pinch.
Habitat & Behavior
Habitat & Range
Commonly found in North America (especially the Pacific Northwest) and Europe. Prefers dark, dry environments like basements, attics, sheds, and stone walls.
Behavior & Temperament
Extremely fast runners but generally timid. They are active hunters at night. They are not aggressive and will typically flee or 'play dead' when confronted by humans.
Diet & Prey
Generalist predators feeding on flies, mosquitoes, moths, beetles, and even other spiders including the Hobo Spider and Black Widows.
Seasonal Activity
Active year-round indoors, but most visible in late summer and autumn (August to October) during the mating season.
Description
The Giant House Spider is a common sight in autumn when males wander indoors searching for mates. Despite their intimidating size and speed, they are beneficial house guests that provide free pest control.
Key Features
Large leg span, mottled brown abdomen with chevrons, lack of leg banding, and long prominent spinnerets.
Similar Species
Hobo Spider (Eratigena agrestis) which is smaller with shorter legs; Domestic House Spider (Tegenaria domestica) which has banded legs and is smaller.
Life Cycle
Females produce several white, lens-shaped egg sacs. Spiderlings emerge and stay near the web initially. They can live 2-3 years, which is longer than many other temperate spider species.
Ecological Importance
Crucial nocturnal predator that maintains insect populations and actively out-competes more medically significant spiders like the Hobo Spider.
Conservation Status
Not evaluated by IUCN; common and stable throughout its range.
Interesting Facts
For a long time, the Giant House Spider held the Guinness World Record for the fastest spider speed (approx 1.73 ft/s) before being surpassed by Camel Spiders.
Photography Tips
Focus on the dorsal (top) pattern of the abdomen and the cephalothorax stripes. Use a side angle to capture the length of the spinnerets for accurate genus identification.
Identified: 2026-05-23T11:03:12.929642