Spider With a White Stripe? How to Identify a White-Tailed Spider

You’ve spotted a dark, fast-moving spider with a small white mark at the end of its tail — and now you want to know what it is and whether you should be worried. The short answer: it’s a white-tailed spider, and its fearsome reputation is largely undeserved.

Here’s how to identify a spider with a white stripe or spot, the truth about their bite, and how to keep them out of your Southern Adelaide home.

What a White-Tailed Spider Looks Like

A spider with a white spot or stripe at the tip of its tail is almost certainly a white-tailed spider. They’re one of the easiest spiders to identify once you know the marking.

• Body: dark reddish-grey to almost black, cigar- or torpedo-shaped, roughly 12–18mm long.
• The marking: a distinct pale, greyish-white spot right at the tip of the abdomen — the “white tail” that gives them their name.
• Juveniles: may show additional faint pale bands on the body as well as the tail spot.
• Legs: dark, often with a slightly banded or reddish tint near the body.

Because they’re active hunters, you’ll usually see them moving across a wall or floor at night rather than sitting in a web.

Is It a Stripe or a Spot?

Most people search for a “spider with a white stripe”, but on an adult white-tailed spider the marking is really a single pale spot at the very tip of the tail. Younger spiders can show a couple of fainter pale patches further up the body, which is where the “stripe” description comes from. Either way, the pale mark at the end of the abdomen is the giveaway.

Are White-Tailed Spiders Dangerous?

No — the flesh-eating ulcer reputation is a myth. For years, white-tailed spiders were blamed for severe necrotic (skin-destroying) ulcers. But a major Australian study that followed more than 130 confirmed white-tailed spider bites found not a single case of ulceration.

In reality, a white-tailed spider bite usually causes:

• Short-lived local pain, similar to a bee sting;
• Redness, mild swelling, and an itchy spot;
• Symptoms that settle on their own within a day or so.

As with any bite, see a doctor if the pain is severe, if symptoms spread or worsen, or if you’re worried — but there’s no need to panic about a white-tailed spider in the house. If spiders in general make you uneasy, our honest guide to huntsman spider danger and myths covers another commonly-feared local spider.

Why White-Tailed Spiders Come Inside

White-tailed spiders come indoors for one main reason: to hunt other spiders. Their favourite prey is the black house spider, so a home with a healthy spider population is an attractive hunting ground. Because they don’t spin webs to catch food, they roam — across ceilings, down walls, and sometimes into clothing, towels or bedding left on the floor.

That’s the key insight for control: if you’re seeing white-tailed spiders regularly, you likely have plenty of other spiders feeding them.

How to Keep White-Tailed Spiders Out

Removing their food and hiding spots is the most effective approach:

• Clear webs from around the house, eaves, and window frames to reduce the spiders white-tails feed on.
• Seal gaps around doors, windows and vents.
• Shake out clothing, towels and shoes left on the floor before use.
• Keep beds slightly away from the wall and avoid storing items underneath.
• Reduce outdoor lighting that attracts the insects other spiders feed on.

For a seasonal plan, our guide on how to prevent spiders in winter has more detail on keeping numbers down year-round.

When to Call a Professional

Regular white-tailed spider sightings are a sign of a broader spider population in and around your home. A professional treatment targets both the white-tails and the spiders they hunt, breaking the cycle. Our spider management service covers Seaford and Southern Adelaide from $270, treating nesting areas, entry points and the perimeter so spiders have nowhere to settle.

Hero image: “White-tailed spider” by CSIRO, licensed under CC BY 3.0.