Grey House Spider, Window Spider
Badumna longinqua (or related Badumna / Amaurobiidae species)
Desidae (Intertidal and House Spiders), Order Araneae. Formerly often placed in Amaurobiidae. Characterized by cribellate or related silk production structures and funnel-weaving habits.
Physical Description
Compact, robust body with a distinct oval abdomen and a somewhat flattened, sturdy cephalothorax. The spider has a dense velvety texture due to fine hairs covering the body.
Size Estimate
Body length approximately 10 to 15 mm with a leg span of around 25 to 35 mm. Appears to be a sub-adult or adult specimen.
Coloration & Markings
Dark grey to charcoal brown overall coloration, often featuring subtle mottled or chevron patterns along the dorsal surface of the abdomen, though sometimes appearing entirely dark in low light.
Web Type
Messy, lace-like funnel web or cribellate sheet web with a tubular retreat, frequently built in corners of window frames, crevices, tree bark, and rough surfaces.
Eye Arrangement
Eight small eyes arranged in two slightly curved rows across the broad front of the cephalothorax, typical of cribellate funnel-weavers.
Leg Characteristics
Sturdy, moderately long legs with dense hair coverage, held close to the body in a crouched resting posture when waiting in the web retreat.
Venom & Safety Information
Venom Information
Contains neurotoxic components typical of cribellate spiders. While venom is used effectively to subdue insect prey, envenomation of humans is rare.
Medical Significance
Not medically significant. Bites are uncommon and typically only occur if the spider is accidentally trapped against the skin. Symptoms are usually minor local pain and swelling.
Safety Recommendations
Simply leave the spider alone if it is out of the way. If relocation is necessary, gently guide it into a container using a piece of card.
Habitat & Behavior
Habitat & Range
Native to Australasia but introduced globally in temperate urban environments. Found commonly on buildings, fences, tree trunks, and around window frames.
Behavior & Temperament
Reclusive, nocturnal ambush predator. Stays hidden inside its tubular retreat until prey triggers the cribellate silk web. Non-aggressive towards humans.
Diet & Prey
Primarily feeds on flying insects such as flies, moths, mosquitoes, and beetles that become entangled in the sticky lace-like web.
Seasonal Activity
Active year-round in temperate indoor environments, with peak web-building and foraging activity occurring during the warmer spring and summer months.
Description
The Grey House Spider is a common urban dweller known for constructing distinct lace-like funnel webs in corners and around windows. Its velvety dark body and reclusive nature make it a fascinating, quiet neighbor that helps control household insect populations.
Key Features
Velvety dark body, compact robust proportions, and the characteristic lace-like funnel web built in angular crevices or window corners.
Similar Species
Tegenaria species (Hobo Spiders/Giant House Spiders) and Agelenidae family members, which build larger non-cribellate funnel webs with longer, more tapered spinnerets.
Life Cycle
Females construct silken egg sacs hidden near the web retreat. Spiderlings disperse via ballooning or crawling short distances after hatching. Lifespan typically ranges from one to two years.
Ecological Importance
Serves as an effective natural pest controller in domestic and garden environments, consuming large numbers of nuisance flying insects.
Conservation Status
Not threatened; highly adaptable and successfully established in urbanized areas across multiple continents where introduced.
Interesting Facts
These spiders use a specialized spinning organ called a cribellum to produce a woolly, blue-grey silk that lacks glue droplets yet effectively snags insect tarsi.
Photography Tips
Use macro lenses with adequate lighting to capture the fine velvety hair texture and eye arrangement. Photograph from a slight angle to highlight the tubular web retreat.
Identified: 2026-09-06T06:28:11.637564