Giant House Spider
Eratigena atrica
Agelenidae (Funnel-web weavers), Order Araneae. Key family characteristics include three pairs of spinnerets with the posterior pair notably elongated, and an asymmetrical layout of eight eyes in two rows.
Physical Description
Robust body with a hairy texture, long legs, and a brownish cephalothorax featuring indistinct lighter markings. The elongated abdomen is typically patterned with mottled yellowish-brown markings.
Size Estimate
Body length ranges from 10 to 18 mm for females (sometimes up to 20 mm) with a leg span reaching up to 75 to 100 mm. This appears to be an adult specimen, likely a male given the prominent palps.
Coloration & Markings
Various shades of brown, dirty yellow, and grey. The cephalothorax features pale, indistinct markings, and the abdomen has a chevron or mottled pattern down the dorsal side.
Web Type
Messy, non-sticky sheet web (funnel web) leading to a tubular retreat where the spider hides, usually constructed in dark corners, behind furniture, or in basements.
Eye Arrangement
Eight small, dark eyes arranged in two slightly curved, horizontal rows of four across the front of the carapace.
Leg Characteristics
Long, robust legs covered in visible hairs and spines, uniform brown without distinct banding, held spread out in a typical sprawling posture.
Venom & Safety Information
Venom Information
Neurotoxic venom primarily used to immobilize insect prey. It is low in potency relative to humans and rarely causes systemic issues.
Medical Significance
Harmless to humans. Bites are extremely rare and typically only occur if the spider is trapped directly against the skin. Symptoms are usually mild, similar to a mosquito bite or slight localized pain.
Safety Recommendations
Avoid handling them bare-handed to prevent accidental bites. If relocation is needed, place a glass over the spider, slide a piece of paper underneath, and release it outdoors.
Habitat & Behavior
Habitat & Range
Found widely across Europe and introduced to parts of North America (especially the Pacific Northwest). Prefers dark, undisturbed human structures, cellars, sheds, and damp natural crevices.
Behavior & Temperament
Fast-moving, nocturnal hunter that relies on its sheet web to detect vibrations of passing prey. Generally docile and reluctant to bite, but can move extremely quickly if startled.
Diet & Prey
Insects and other arthropods, including cockroaches, flies, silverfish, and other spiders, captured by rushing out from the funnel retreat when prey triggers the web.
Seasonal Activity
Most commonly seen wandering in late summer and autumn (August to October) when mature males leave their webs in search of females.
Description
The Giant House Spider is one of Europe's largest common indoor spiders. Known for its impressive leg span and surprising speed, it is a master of dark corners and quiet basements. While its intimidating appearance often startles homeowners, it serves as a beneficial predator that helps keep household pest populations under control.
Key Features
Large size, long hairy legs, uniform brown coloration without bright warning patterns, and construction of a flat sheet web ending in a funnel-like retreat.
Similar Species
Tegenaria domestica (Barn Funnel Weaver) which is generally smaller and has distinct banding on the legs and palps. Can also be confused with Wolf Spiders (Lycosidae), which do not build webs.
Life Cycle
Females lay eggs inside a silk egg sac in autumn. Spiderlings hatch in spring, molt multiple times, and reach maturity in two to three years. Adults often wander indoors during late summer and autumn looking for mates.
Ecological Importance
Acts as a top-tier indoor and peridomestic pest controller, actively reducing populations of flies, roaches, and other household insects.
Conservation Status
Not evaluated by the IUCN, but populations are robust, widespread, and thriving in association with human habitations.
Interesting Facts
Giant House Spiders held the Guinness World Record for top spider speed, capable of sprinting at over 1.73 feet per second (0.5 meters per second).
Photography Tips
Use natural lighting or an off-camera diffuser to capture the fine hairs on the legs and body. Maintain a safe distance to avoid startling the spider into a rapid escape.
Identified: 2026-09-18T06:27:08.367726