The redback spider (Latrodectus hasseltii) is a dangerous spider endemic to Australia. It is a member of the genus Latrodectus, the widow spiders, which are found throughout the world. The female is easily recognisable by her black body with a prominent red stripe on the upper side (i.e. the back) of her abdomen.
Redbacks are considered one of the most dangerous species of spider in Australia. The redback spider has a neurotoxic venom that is toxic to humans with bites causing severe pain, often for over 24 hours. An antivenom is commercially available, and since its introduction in 1956 there have been no deaths due to Redback bites.