Giant House Spider
Eratigena duellica (or Eratigena atrica group)
Agelenidae (Funnel Weavers), Order Araneae
Physical Description
A large, robust spider with a relatively small cephalothorax and elongated oval abdomen. The body is covered in fine, short hairs giving it a velvety appearance. Females are bulkier, while males have smaller bodies and significantly longer legs.
Size Estimate
Body length 10-18mm; leg span can reach up to 75-100mm (3-4 inches). Based on the image, this appears to be a mature male given the long, spindly leg proportions.
Coloration & Markings
Dull earthy tones of brown, tan, and grey. The cephalothorax features three light spots on each side near the margin. The abdomen usually has a central light stripe with dark, chevron-like patterns or mottling on either side.
Web Type
Messy, flat horizontal sheet web that leads into a silk-lined funnel-shaped retreat in a corner or crevice. They do not have 'sticky' silk but rely on speed to catch prey.
Eye Arrangement
Eight eyes in two nearly straight rows of four. The eyes are relatively small and equal in size, typical of family Agelenidae.
Leg Characteristics
Notably long and hairy but lacking the thick spines seen in wolf spiders. In males, the legs are exceptionally long relative to the body size. They are built for high-speed sprinting.
Venom & Safety Information
Venom Information
Possess a mild venom used to subdue insects. It is not considered toxic to humans and is generally less potent than a common bee sting.
Medical Significance
Harmless. Bites are extremely rare and usually only occur if the spider is squeezed. Symptoms are typically limited to minor localized redness, swelling, and itching.
Safety Recommendations
If found indoors and unwanted, use the 'cup and paper' method to relocate them outside. They are beneficial for the garden and pose no risk to children or pets.
Habitat & Behavior
Habitat & Range
Commonly found in Europe and the Pacific Northwest of North America. They prefer dark, undisturbed areas such as garages, basements, woodpiles, and behind heavy furniture.
Behavior & Temperament
Extremely fast runners but generally shy and non-aggressive. They will typically flee toward a dark corner when disturbed. They are active primarily at night.
Diet & Prey
Generalist predators feeding on various household insects including flies, beetles, and even other spiders. They use their speed to overpower prey that vibrates their sheet web.
Seasonal Activity
Sightings peak in late summer and autumn (August-October) when mature males wander out of their webs in search of females for mating.
Description
The Giant House Spider is one of the fastest invertebrates in the world, capable of bursts of speed up to 1.7 feet per second. Despite their intimidating size, they are beneficial roommates that provide excellent pest control.
Key Features
Large leg-to-body ratio, chevron abdomen pattern, and the visible spinnerets at the rear of the abdomen which are typical of funnel weavers.
Similar Species
Often confused with the Hobo Spider (Eratigena agrestis), which is smaller and lacks the distinct dark spots on the sternum. Also confused with Wolf Spiders, which have much larger eyes and do not build webs.
Life Cycle
Females produce several white, papery egg sacs. Spiderlings emerge and may stay near the mother for a short time. They can live for 2-3 years, which is longer than many other temperate spider species.
Ecological Importance
Crucial for controlling indoor and perimeter insect populations. They serve as a natural, chemical-free way to manage earwigs, flies, and moths.
Conservation Status
Not evaluated by IUCN; widely distributed and common across its range with no known threats.
Interesting Facts
Until 1987, it held the Guinness World Record for the fastest spider speed. They are known to 'run' across rooms so quickly they startle residents, though they have no interest in humans.
Photography Tips
A top-down (dorsal) view is best for seeing the abdomen patterns and cephalothorax markings. Use a flashlight to illuminate the fine hairs and eye arrangement.
Identified: 2026-06-21T03:36:51.257649