What are Mouse Spiders? Identification, Bites and First Aid
According to the Australian Museum, the Mouse Spider (genus Missulena) is a stout, burrow-dwelling spider found across much of mainland Australia. Known for its powerful jaws, it is often searched for due to concerns about bites and first aid responses.
Mouse spiders are also often mistaken for Funnel-web spiders because they have almost the same size, colour and hunting habits.
What is a Mouse Spider?
A mouse spider is a mygalomorph spider of the genus Missulena native to Australia.
Quick Facts:
- Genus: Missulena (family Actinopodidae)
- Size/Appearance: Females often ~30-35 mm body length; males are usually smaller but more mobile. They also have glossy and smooth carapace with the eyes spread out at the front.
- Behaviour/Burrows: Builds silk-lined burrows with a trap-door or side-chamber; males wander in search of mates.
- Seasonality: Males wander late summer to early winter (particularly after rain); females remain in burrows.
Where Do Mouse Spiders Live in Australia?
Mouse spiders are found across mainland Australia in a variety of habitats.
- States/Territories: Found in Western Australia, South Australia, New South Wales, Victoria, Queensland, Northern Territory.
- Typical habitats: Open forest, semi-arid shrubland, suburban gardens, riverbanks where burrows can form.
Are Mouse Spiders Dangerous?
Yes, you should treat a suspected mouse spider bite seriously but the odds of a life-threatening outcome are low. Most bites cause mild to moderate symptoms, and fatalities are not recorded.
Practice caution, apply first aid, and seek medical attention.
What are the Mouse Spider Bite Symptoms?
Mouse spider bites have similar symptoms to those of a Redback spider. Symptoms may develop within minutes to hours after a bite.
- Pain at the bite site
- Redness
- Swelling
- Tingling
- Numbness
- Sweating
- Muscle spasms
- Nausea
- Headache
- Elevated blood pressure, particularly in children
What is the First Aid for a Mouse Spider Bite?
Mouse spider bites should be treated as an emergency. Use the Pressure Immobilisation Technique (PIT):
- Keep the person still and calm. Movement increases venom spread.
- Place a broad, firm pressure bandage over the bite site, high on the limb if possible.
- Immobilise the entire limb, you may use a splint or sling, and keep it lower than heart level.
- Call 000 immediately and inform ambulance service it may be a mouse spider (or funnel-web) bite.
- Do not wash off the venom marks as identification may assist treatment.
What not to do:
- Do not apply a tourniquet that completely stops blood flow.
- Do not cut into the bite wound or try to suck out venom.
- Do not give alcohol or medication unless instructed by medical professionals.
When to Call Triple Zero (000) or Seek Urgent Care
- If the bite site is on a child or elderly person.
- If systemic symptoms like trouble breathing, signs of anaphylaxis, heavy sweating, muscle spasms, fainting appear.
- If you are unsure which spider bit you and symptoms are progressing.
- If antivenom may be required (hospital will assess).
How to Prevent Mouse Spider Bites?
- Wear gloves, boots and long sleeves when gardening, clearing debris or lifting logs.
- Inspect shoes, gloves, and sleeping bags before use especially at night.
- Seal holes in shed floors or garage walls where spiders may burrow.
- Avoid leaving outdoor furniture pushed up against garden soil walls.
- If relocating heavy objects (rocks, logs, building materials) do so carefully. Tap surfaces before lifting.
Conclusion
Mouse spiders might look intimidating, but serious bites are rare. Stay calm, use the Pressure Immobilisation Technique (PIT), and call triple zero (000) right away.
Wearing protective gear and knowing basic first aid can help keep you and your family safe. For extra confidence, take a certified First Aid and CPR course, it’s the best way to be prepared for any emergency.
FAQs
Do mouse spiders chase humans?
No, they are not actively aggressive hunters of humans. Most incidents occur when humans accidentally disturb their burrow or grab them.
Can pets be affected?
Yes, pets can be bitten if they roll over a spider or disturb its habitat. Apply the same first aid and seek veterinary care.
How common are mouse spider bites?
Very rare compared to other spider bites. Serious envenomations number only a handful of documented cases.
What if I can’t identify the spider that bit me?
Assume the worst case (funnel-web or mouse spider) if you are in a habitat that supports them. Use pressure immobilisation and seek urgent medical attention.
Do I need a tetanus shot after a spider bite?
A tetanus booster may be advised especially if the bite wound is deep, contaminated with soil/mulch, or you haven’t had a booster in the past 10 years. Ask your GP.