White-tailed spider (Lampona species)

White-tailed spiders are a venomous spider introduced to New Zealand from  Australia.

There are actually two common white-tailed spider species – Lampona cylindrata and Lampona murina – which need expert identification to distinguish. Lampona murina is more widely distributed in New Zealand.

Their natural habitat is underneath bark and rocks and in the leaf litter, where they hunt for their prey. When they find their way into homes, sheets and clothing (especially left on the floor) are favoured hiding spots as they are similar to their natural resting places.

White tail spiders have a dark grey to black, slim and elongated body, with two pairs of faint white spots on the abdomen and a white spot at the tip. The leg coloration is dark orange / brown bands.

The female body length is up to 18 mm (leg span up to 28 mm) and the male up to 12 mm.

Web:

White-tailed spiders do not build webs – they are considered a running or hunting spider.

Mating:

The male spider approaches the female from the front but will only approach if they get an appropriate signal from the female (otherwise they could end up being dinner).

Eggs:

The females make temporary silk retreats where she lays up to 90 eggs in a disc-shaped egg sac.

White-tailed baby spiders:

The female spider guards the egg sac until the baby white-tails or spiderlings emerge. As soon as they disperse they are off to find their first meal.

Life-span:

White tails are not tolerant of cold weather and many die off over winter in colder areas. It is assumed they generally live for no more than a couple of years.

White tailed spiders are hunting spiders and target other spiders as their prey, with black house spiders and grey house spiders considered their preferred prey. For this reason they are often found in and around houses in summer and autumn when black house spiders numbers are at their peak.

They are a nocturnal hunter (most active at night).

White tails have a very painful bite, however there is no evidence that the white tailed spider bite cause necrotic ulcers (where the flesh gets eaten away). There are no toxins in the white tail spider venom that can cause ulcers. Of 130 confirmed bites in a scientific study, none produced a skin ulcer.

It is believed that ulcers may form after any spider bite, and are probably due to infection from bacteria, which has been introduced into the bite through scratching, dirt or possible off the spider’s fangs.

Isbister, G.K. & Gray, M.R. 2003. White-tail Spider bite: a prospective study of 130 definite bites by Lampona species. Medical Journal of Australia 179: 199-202.

Symptoms:

The white tail spider bite causes a painful initial burning pain, followed by swelling and itchiness at the bite site.

First aid:

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

Keeping spider webs in check in around the home will reduce the number of potential prey items around to attract white-tail spiders. Keeping clothes and bedding off the floor is a good idea too!