Redback Spiders(Latrodectus hasselti) By Genevieve
Description Redback spiders belong to the Family Theridiidae which can be found all around the world. The Redback spider is one of Australia’s most common species and is found in the bush and the city. They have a distinctive longitudinal red or white stripe on their upper abdomen.
Description Mature female Redback spiders are black with a red stripe on there upper abdomen and can grow up to 1 centimetre. Immature female Redback spiders are smaller and usually brown with white markings. Male Redback spiders are brown with red and white markings. They can grow 3 to 4 millimetres in size.
Their Food Redback spiders usually eat insects. They are able to capture larger animals such as male trapdoor spiders, king crickets and small lizards if they become entangled in their webs. Prey-stealing is also common with large female redback spiders taking stored food from others’ webs.
Where they live Redback spiders are found all around Australia and live almost anywhere as long as there is adequate food and a good sheltered warm place for breeding. In the bush they nest under logs and rocks. In the city they can be found in dry places around buildings, outdoor furniture and machinery.
Their Web A web is made of vertical, sticky catching threads. Females make a funnel shaped web. Built in dry, sheltered places such as rocks, logs or toilets.
Their Life Cycle The male spider hangs around near a female's web. He gets the female spider’s attention by showing her his abdomen. Many males are eaten as they mate! Once the female has mated she makes about 10 white egg sacs, 1 every 3 weeks or so. Each sac has about 250 eggs. The sacs hang in the web. When they hatch the tiny, pale-green spiderlings balloon away on silk threads. Female redbacks live for about 2-3 years. Males live for about 6-7 months.
Theirbite-venom Only the female red back spider bite is dangerous. If bitten the venom can cause in pain, sweating, nausea, vomiting and even death. Antivenom medicine is available.
Other Interesting information They are a close relative of the Black Widow Spider found in the USA. Redback spiders are not aggressive and rarely leave the web. Bites usually occur when part of the body comes in direct contact with the spider or its web.
A female red back spider The male redback spider is only about one-third the size of the female.