Grey House Spider, Brown House Spider
Badumna longinqua
Desidae (Intertidal and House Spiders), Order Araneae
Physical Description
Robust, stout-bodied spider with a smooth, dark carapace and a densely haired, oval abdomen. The cephalothorax is dark brown to black, while the abdomen is typically greyish-brown with a mottled pattern.
Size Estimate
Body length ranges from 9 to 18 mm for females, with a leg span of approximately 25 to 35 mm. The specimen pictured appears to be an adult.
Coloration & Markings
Dark brown to charcoal black cephalothorax and legs, with a lighter greyish-brown abdomen featuring a distinct longitudinal patterned marking or mottled chevron designs down the dorsal center.
Web Type
Messy, lace-like sheet webs with a tubular retreat retreat leading into a crevice or hole, commonly built in window frames, corners, and bark crevices.
Eye Arrangement
Eight eyes arranged in two slightly curved rows of four, typical of cribellate spiders, with similar-sized eyes spread across a broad head region.
Leg Characteristics
Robust and moderately long legs with distinct dark banding or a uniform dark coloration, covered in fine hairs and strong spines used for navigating their dense webs.
Venom & Safety Information
Venom Information
Possesses mild neurotoxic venom used to subdue insect prey. Envenomation in humans is rare and typically mild, causing localized pain, swelling, and redness.
Medical Significance
Not medically significant. Bites are uncommon and usually occur only when the spider is accidentally pressed against the skin. Symptoms rarely progress beyond localized discomfort, though rare cases may involve nausea or localized sweating.
Safety Recommendations
Avoid direct handling with bare hands. If found inside, gently capture under a container and release outdoors in a sheltered garden area. Seal home entry points to reduce indoor encounters.
Habitat & Behavior
Habitat & Range
Originally native to Australia and New Zealand, now widely introduced globally including North America, Europe, and South Africa. Frequently found around human habitations, on walls, fences, and tree bark.
Behavior & Temperament
Reclusive, nocturnal ambush hunters. They spend most of their time hidden inside their tubular retreats, waiting for prey to land on the sheet web. Generally non-aggressive unless provoked or trapped against skin.
Diet & Prey
Primarily feeds on common household insects such as flies, moths, mosquitoes, beetles, and other small arthropods that become entangled in the web.
Seasonal Activity
Active year-round, especially in heated indoor environments, with peak foraging and web-building activity observed during the warmer spring and summer months.
Description
The Grey House Spider is a familiar yet elusive nocturnal arachnid that has successfully adapted to coexisting with humans around homes and buildings. Known for constructing characteristic messy, funnel-like webs in corners and window frames, this robust dark spider serves as an efficient natural pest controller. While their appearance can be startling due to their dark color and sturdy build, they are generally shy and pose virtually no threat to humans.
Key Features
Robust dark body, greyish mottled abdomen, distinctly messy sheet web with a tubular retreat, and a strong association with human structures and bark crevices.
Similar Species
Tegenaria species (Hobo spiders or Giant House Spiders) and Kukulcania hibernalis (Southern House Spider), distinguished primarily by web structure and subtle cephalothorax proportions.
Life Cycle
Females construct papery egg sacs hidden within the retreat webbing. Spiderlings disperse shortly after hatching. They undergo multiple molts over a multi-year lifespan, often living for several years in stable indoor environments.
Ecological Importance
Acts as an effective urban and domestic predator, helping control populations of flies, mosquitoes, and other nuisance insects around human dwellings.
Conservation Status
Not evaluated by the IUCN, but populations are highly abundant, secure, and actively expanding globally through human-mediated transport.
Interesting Facts
Despite being native to Australasia, they are expert hitchhikers and have established thriving populations in urban environments worldwide. They often share their webs with small scavenging pirate spiders.
Photography Tips
Photograph in natural light or with a diffused flash. Capture dorsal views to show abdominal markings and side angles to highlight the leg structure and robust body shape while the spider is safely contained.
Identified: 2026-08-16T09:15:14.279378