Mouse spider

Australian Mouse Spiders

Powerful burrowers of the bush

On a warm evening after rain, the soil at the edge of a bush track may shift slightly. From a silk‑lined burrow, a stocky spider waits — glossy, low to the ground, and rarely seen. This is the Australian mouse spider, one of the country’s most robust and misunderstood spiders.

Mouse spiders belong to the genus Missulena and are part of Australia’s unique group of mygalomorph spiders, relatives of funnel‑webs and trapdoor spiders.

Where Mouse Spiders Are Found

Mouse spiders occur across mainland Australia, including:

Western Australia
South Australia
Victoria
New South Wales
Queensland

They are most common in:

Open bushland
Grasslands
Heathlands
Urban gardens with undisturbed soil

They live almost entirely underground, emerging mainly after rain.

Appearance and Identification

Mouse spiders are unmistakably solid in appearance.

Key features:

Thick, muscular legs
Large, powerful fangs
Smooth, glossy bodies
Females: usually dark brown or black
Males: often have bright red or orange jaws (chelicerae)

Despite the name, they are not named after mice, but possibly for their mouse‑like burrows or stout shape.

Species Diversity

There are over 40 known species of mouse spiders in Australia.

Well-known examples include:

Eastern mouse spider (Missulena bradleyi)
Red‑headed mouse spider (Missulena occatoria)

Many species are still poorly studied due to their secretive lifestyle.

Burrows and Daily Life

Mouse spiders are expert diggers.

Their burrows:

Are silk-lined
Often have a hinged trapdoor or open entrance
Can be surprisingly deep
Provide protection from heat, predators and drought

They wait just inside the entrance, sensing vibrations through the ground.

What Mouse Spiders Eat

Mouse spiders are ambush predators.

Their prey includes:

Insects
Beetles
Other spiders
Small invertebrates

When prey passes near the burrow, the spider lunges forward with speed, dragging it underground.

Breeding Behaviour

Breeding usually occurs after heavy rain.

Males leave their burrows to search for females
During this time, males may wander into yards, houses or swimming pools
Females lay eggs inside the burrow and guard them

Males typically die shortly after mating.

Longevity

Mouse spiders are long‑lived:

Females: up to 10 years or more
Males: usually shorter-lived, dying after mating

Their slow growth reflects their underground lifestyle.

Venom and Human Safety

Mouse spiders are highly venomous, and their venom is similar in strength to that of funnel‑web spiders.

Important facts:

Bites are very rare
Serious envenomation is uncommon
The funnel‑web antivenom is effective for mouse spider bites
Most bites occur when spiders are handled or trapped

Important safety message:
Mouse spiders should never be handled. Any suspected bite requires immediate medical attention.

Indigenous Knowledge and Cultural Context

For Aboriginal Australians, burrowing animals were important indicators of soil health and seasonal change.

Spiders living underground were observed as part of Country’s hidden life
Their emergence after rain signalled shifts in weather and insect activity
Respect and avoidance, rather than fear, guided interactions

This deep observational knowledge helped people live safely alongside potentially dangerous species.

Interesting Facts About Mouse Spiders

🕳️ Females may remain in the same burrow for most of their lives
🔴 Some males have bright red jaws used in mating displays
💧 Rain triggers surface activity
🧬 They are ancient spiders with lineage dating back millions of years
🧪 Their venom has been studied for medical research

Why Mouse Spiders Matter

Mouse spiders play a valuable ecological role:

They help control insect populations
Their burrows improve soil aeration
They are part of Australia’s unique evolutionary history

Understanding mouse spiders replaces fear with respect. These powerful, secretive animals are not aggressive — they are simply highly specialised survivors of Australia’s ancient landscapes.