Black House Spider

IUCN

Scientific Name：Badumna insignis

Basic Information

Scientific classification

name：Black House Spider
Scientific Name：Badumna insignis
Outline：Arthropoda
Family：Desidae Badumna

Vital signs

length：Females 14–18 mm; males 10–12 mm (excl. legs)
Weight：Small–medium spider; varies with individual
lifetime：About 1–2 years; females often longer

Feature

Nocturnal; urban‑tolerant; cribellate woolly silk tangled sheet + funnel retreat; exploits light‑attracted insects.

Distribution and Habitat

Australia (native) and New Zealand (introduced); eaves, frames, bark crevices, timber and rock walls in urban/suburban sites.

Appearance

Dark brown to blackish; pale setae/markings on carapace; mottled abdomen; messy sheet web with tubular retreat.

Details

The Black House Spider (Badumna insignis) is a desid spider native to Australia, frequently found around eaves, window frames, door gaps, fences and bark crevices. It is a web‑building ambush predator that spins cribellate, woolly silk forming a tangled sheet with a tubular/funnel retreat, from which it intercepts prey.

Ecology & Biology

Activity: mainly nocturnal; often constructs webs near lights to catch moths and mosquitoes.
Diet: moths, midges, mosquitoes and beetles. The web is non‑sticky; capture relies on the hackled cribellate fibers entangling prey.
Reproduction: females build and guard egg sacs near the retreat; spiderlings disperse around the maternal web.

Identification

Body length: females 14–18 mm; males 10–12 mm (excluding legspan).
Colour: overall dark brown to blackish; carapace with pale setae and fine markings; abdomen mottled darker.
Silk/web: possesses a cribellum and calamistrum to produce woolly cribellate silk; web a messy sheet leading to a tubular retreat.

Range & Habitat

Native and widespread in Australia; introduced to New Zealand and recorded in other regions. Common in urban/suburban sites on walls, frames, timber piles, rock walls and under bark.

People & Safety

Medical relevance: generally low to moderate; bites cause local pain and swelling. It is not related to the medically significant Australian funnel‑web spiders (Atracidae).
Advice: fit screens, reduce night‑lighting or insect attraction, and remove old webs; relocate spiders gently with a cup‑and‑card.

IUCN: Not Evaluated (NE).

FAQ

Q1. Do they attack people? No—typically reclusive inside the retreat; bites occur only when provoked or trapped.

Q2. Related to dangerous funnel‑webs? No. Black house spiders are Desidae, much smaller with different web structure and far lower medical importance.

Q3. How to prevent indoors? Maintain screens, reduce light spill, clean frames and old webs to lower insect attraction.

Q4. What to do after a bite? Wash, apply a cold pack and monitor; seek medical advice if symptoms persist.