Giant House Spider
Eratigena duellica (formerly Tegenaria gigantea)
Agelenidae (Funnel-Web Spiders), Order Araneae. Characterized by long spinnerets and sheet-like webs ending in a funnel.
Physical Description
A large, robust spider with a hairy appearance. The cephalothorax is pear-shaped and the abdomen is oval. The specimen in the image appears to be a male, noted by the enlarged pedipalps (looking like small boxing gloves) used for mating.
Size Estimate
Giant House Spiders can reach a body length of 12-18mm for females and 10-15mm for males. Including legs, the span can reach 2-4 inches (50-100mm). This appears to be an adult male.
Coloration & Markings
Generally earthy tones of brown, tan, and grey. The cephalothorax often features two dark longitudinal stripes. The abdomen has a series of 'chevrons' or speckles (carden patterns). Legs are usually solid brown without distinct rings, though mottling occurs.
Web Type
Funnel web. They build a flat sheet of non-sticky silk that leads into a silk tube or funnel in a corner or crevice where the spider hides.
Eye Arrangement
Eight eyes of similar size arranged in two rows of four. The rows are generally slightly curved, though hard to see without macro magnification.
Leg Characteristics
Long, hairy legs that are quite fast. Unlike the related hobo spider, the Giant House Spider's legs are typically not banded but may have very light mottling. The hairs are sensory setae used to detect vibrations.
Venom & Safety Information
Venom Information
Neurotoxic venom used to paralyze insect prey. However, the venom is not considered medically significant to humans and is far less potent than that of a Latrodectus (widow) species.
Medical Significance
Low. A bite may cause minor localized pain, swelling, or redness, similar to a bee sting. They are often confused with the Hobo Spider, but neither is considered dangerous to healthy humans.
Safety Recommendations
If found indoors and unwanted, they can be easily relocated using a cup and a piece of paper. Since they are harmless, no special safety gear is required, though handling with bare hands isn't recommended to avoid accidental bites.
Habitat & Behavior
Habitat & Range
Found throughout Europe, Central Asia, and Northern Africa. It was introduced to North America, where it is common in the Pacific Northwest and parts of the East Coast. Prefers dark, undisturbed areas like basements, sheds, and behind furniture.
Behavior & Temperament
They are incredibly fast runners (one of the fastest spiders for their size). They are generally shy and will retreat into their funnel at the slightest vibration. They are not aggressive toward humans and usually bite only if squeezed.
Diet & Prey
Generalist predators eating house flies, moths, beetles, and even other spiders. They sit in their funnel and dash out when they feel vibrations on the sheet web.
Seasonal Activity
Active year-round indoors, but most visible in August through October when males leave their webs to search for females.
Description
The Giant House Spider is a common, large arachnid often found indoors during the autumn. Despite their intimidating size and speed, they are beneficial roommates that provide free pest control. This male specimen is a typical autumnal wanderer.
Key Features
Large size, long legs, hairy body, and distinct chevron patterns on the abdomen. Long spinnerets at the rear of the abdomen are also a family trait.
Similar Species
Eratigena agrestis (Hobo Spider) which is smaller and has different sternum markings. Tegenaria domestica (Barn Funnel Weaver) which is smaller and more heavily marked.
Life Cycle
Males wander in late summer and autumn looking for females (this is when they are most often seen). Females lay eggs in white silk sacs. They can live for 2-3 years, which is longer than many other common house spiders.
Ecological Importance
Critical for indoor and garden pest control. They keep populations of flies, silverfish, and moths in check.
Conservation Status
Not evaluated by the IUCN, but populations are stable and widespread.
Interesting Facts
They were once held the Guinness World Record for the fastest spider (clocked at nearly 1.73 feet per second). They are known to actually hunt and kill hobo spiders, helping to keep those populations in check.
Photography Tips
Capture a top-down view (dorsal) to show the abdomen patterns and a close-up of the front of the cephalothorax to see the pedipalps for sex identification.
Identified: 2026-06-01T00:30:24.652731