redback spider

The red-back spider (Latrodectus hasselti) is a potentially dangerous spider now found throughout Australia. Its origins are uncertain, and it may have been spread by human activities during the 19th century. The notorious Black Widow Spider (Latrodectus sp) of the United States is a close relative of the Redback Spider, and only differs in appearance by the absence of a red dorsal stripe.

A successful bite from a female red-back injects a neurotoxin into the blood stream. Individuals bitten often describe the bite as extremely painful. Despite this (and in contrast to common belief in Australia) deaths from the red-back have been rare: A single death has been reported since the introduction of antivenom in 1956. It is, however, recommended to seek medical attention following a bite. This is particularly true for children, the elderly or those with serious medical conditions since the bite could be much more life threatening to these groups. (wikipedia)

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