Black house spider (Badumna insignis)

The black houses spider is sometimes call the common black spider

Black house spiders and their close relatives grey house spiders are found across the sub-tropical and temperate regions of Australia, from southeast Queensland down to Tasmania and across to Perth. They are occasionally found in warmer, tropical areas.

They are normally found on tree trunks, logs and under rocks although around buildings they are found:

• Around window frames, doors and eaves
• In vents and weep holes
• Along fencing (especially inside tubular fencing)
• Under rocks and wood piles
• In the sub-floor (if you have one)
• Under outdoor furniture and BBQs
• In post boxes and electrical boxes

Female: Body up to 18 mm (with 30 mm leg span)

The black house spider is dark brown / black carapace with a charcoal grey abdomen with white markings / hairs. The females are larger than the males. It’s legs are brown / black. Due to it’s grey coloured abdomen it is sometime called the grey house spider overseas.

There is also the related brown house spider, Badumna longinqua, which has a has a brown carapace (a similar coloured abdomen) and grey-brown banded legs.

Male: Body up to 10 mm

The legs appear longer in relation to the body than the female.

Web:

The black house spider produces messy web, with an obvious a funnel-type centre (which is why homeowners can sometimes be concerned they have a funnel-web spider). The web is generally kept clear of debris.

Mating:

Female black house spiders never leave their webs, so the males need to go looking for a mate. Once they have found a female they pluck the web to get her attention and make sure she is receptive to mating. Once together they tend to remain together for a couple of days, mating several times.

Eggs:

Black house spiders produce egg sacs which are secured within the funnel part of the web.

Baby black house spiders:

The baby redbacks or spiderlings hatch from their eggs within a couple of weeks and disperse. Sometime the spiderlings can remain around the perimeter of the web picking up smaller prey.

Life-span:

Black house spiders live for about 2 years.

Black house spiders will capture and feed on a wide range of insects.

Black house spiders are a timid spider and will retreat quickly into its web when disturbed. However, if bitten it’s bite can be quite painful.

Symptoms:

• Localised pain and swelling
• Occasionally nausea, vomiting, sweating and dizziness

First aid:

• Apply an ice pack to the bite area
• (Capture or take a photo of the spider for identification)
• Seek medical attention if symptoms persist

Black house spiders are a favourite food of white-tail spiders.

Other than keeping rubbish and stored goods away from the perimeter of the property, the only way to eliminate a black house spider problem or prevent them building their webs is with a professional pest treatment.