Fiddleback Spider (Loxosceles rufescens)

what does this mean?  First Aid for envenomation by this species  show the distribution of this species

This spider is so named because of the slight outline of a violin on the front half of its body. It has a delicate appearance and is generally reddish-brown in colour. It is believed that fiddleback spiders have been established in the Adelaide area for some decades. It is not known whether the venom of this species is dangerous to humans, but a closely-related species in North America, the brown recluse spider, has venom which can cause severe reactions and even death.

Loxosceles rufescens