Barn Funnel Weaver, Common House Spider, Giant House Spider
Tegenaria domestica / Eratigena atrica complex
Agelenidae (Funnel-Weavers), Order Araneae. Key family characteristics include three pairs of spinnerets with the posterior pair notably elongated, and an aptitude for constructing funnel-shaped sheet webs.
Physical Description
The spider has an elongated oval abdomen and a distinct, slightly flattened cephalothorax. The body appears finely haired rather than smooth, with robust proportions typical of funnel-weavers. Females tend to be slightly larger and heavier-bodied than males.
Size Estimate
Body length ranges from 6 to 18 mm, with a leg span reaching up to 40 to 50 mm, making it a medium to large house spider.
Coloration & Markings
Base coloration consists of dull brown, beige, or yellowish-brown tones. The abdomen features mottled patterns, often with dark chevron-like markings or spots down the dorsal center, while the cephalothorax typically displays indistinct longitudinal dark stripes or bands.
Web Type
Builds a sheet web that terminates in a tubular retreat or funnel where the spider lurks, commonly constructed in dark, undisturbed corners near the floor, behind furniture, or in basements and bathrooms.
Eye Arrangement
Features eight eyes of roughly equal size, arranged in two transverse curved rows of four along the anterior edge of the cephalothorax.
Leg Characteristics
Long, robust legs covered in fine hairs and spines without prominent contrasting color bands, held in a sprawling posture against surfaces.
Venom & Safety Information
Venom Information
Contains mild neurotoxic and proteolytic venom used primarily to immobilize insect prey. It is not specialized for vertebrate defense.
Medical Significance
Not medically significant. Bites are extremely rare, typically occurring only when the spider is trapped directly against human skin. Symptoms are usually limited to mild, temporary local pain, redness, or swelling comparable to a mosquito bite.
Safety Recommendations
No special precautions needed. If removal is desired, gently guide the spider into a cup using a piece of card and release it outdoors or in an outbuilding.
Habitat & Behavior
Habitat & Range
Cosmopolitan distribution across temperate regions worldwide. Highly synanthropic, frequently found indoors in houses, cellars, barns, garages, and sheds, preferring dark, humid microhabitats.
Behavior & Temperament
Crepuscular and nocturnal hunter. Relies on its sheet web to detect vibrations of prey. Generally timid and fast-moving, preferring to flee into its retreat rather than confront threats, though females guarding egg sacs may show defensive displays.
Diet & Prey
Feeds primarily on household insects including flies, silverfish, cockroaches, beetles, and other spiders caught in its sheet web.
Seasonal Activity
Active year-round indoors, with mature males frequently wandering out in late summer and autumn in search of females, making them most noticeable during these months.
Description
A familiar and harmless inhabitant of human structures, this funnel-weaver is built for speed and agility in dark corners. With its mottled brown tones and sprawling leg stance, it is a master of pest control inside homes, quietly managing insect populations out of sight.
Key Features
Elongated posterior spinnerets, mottled brown chevron patterns on the abdomen, and construction of a flat sheet web with a distinct retreat funnel.
Similar Species
Hobo Spider (Eratigena agrestis) and Wolf Spiders (Lycosidae). Hobo spiders share similar coloration but require detailed structural examination for definitive separation; wolf spiders do not build webs and have different eye arrangements.
Life Cycle
Females construct disc-shaped silk egg sacs containing dozens to hundreds of eggs, often hidden near the web retreat. Spiderlings disperse via ballooning or crawling after hatching. Adults can live for several years, with females living longer than males.
Ecological Importance
Acts as an effective natural pest controller in domestic and agricultural buildings, regulating populations of crawling and flying insects.
Conservation Status
Not evaluated by the IUCN, but highly secure and widespread due to its close association with human dwellings globally.
Interesting Facts
Despite their intimidating size and rapid speed when startled, these spiders are entirely beneficial household residents that rarely venture far from their webs unless searching for mates.
Photography Tips
Use natural lighting or a diffused flash to avoid harsh shadows. Capture dorsal shots to clearly show the abdominal pattern and lateral shots for leg spination and eye arrangement.
User Notes
Found inside house, in bathroom
Identified: 2026-08-13T09:06:24.315961