Oecobius navus
Wall Spider Identification Australia: Oecobius navus
A 2–4 mm flattened wall spider with banded legs and a small flat, star-like web on walls, ceilings, skirting boards and sheltered surfaces.
Usually low riskWall spider and baseboard spider are common names for Oecobius navus, one of Australia’s minute flat-mesh weavers. Adults remain only about 2–4 mm long, so a pinhead-sized spider is not necessarily a spiderling. The strongest everyday identification combines that scale with a broad flattened body, thin banded legs and a roughly circular or star-like web lying flat against a wall or other hard surface. The web often looks like a dusty patch and has openings around its edge. Colour and indoor location alone are weak evidence, and an ordinary photograph may support Oecobius without proving the species.
Quick identification
- Adult body only about 2–4 mm long, measured without the legs
- Broad, low carapace and flattened rounded body with thin legs radiating around it
- Grey, cream or tan mottling with darker rings often visible on the legs
- Flat circular or star-like web, commonly near 3 cm wide, pressed against a hard surface
- Fast short dashes from beneath the web when a signal thread is disturbed
What to check next
Place a ruler beside the web without touching it, then photograph the entire flat web with light coming across the surface. Take a sharp macro view of the spider from above that shows the broad carapace, banded legs and compact central eye group. Record whether it emerged from an edge opening. Do not identify a tiny runner as Oecobius if no web or diagnostic body view is available.
When to seek medical help
Oecobius navus is not among the Australian spiders highlighted by healthdirect as medically dangerous. Avoid handling because its minute size makes injury to the spider more likely than a useful identification. For a suspected bite, wash the area and use a wrapped cold pack for local discomfort. Seek medical advice if pain, swelling or other symptoms are severe, persist or worsen. Call Triple Zero (000) for breathing difficulty, collapse or other signs of anaphylaxis.
Where it is usually seen
Dry sheltered hard surfaces, including walls, ceilings, skirting boards, bathroom and laundry corners, garages, sheds, verandas, masonry, rock faces and the undersides of objects. The flat web can collect dust and may be easier to notice than the spider.