Redback Spider -- Related to the black widow, a bite from Australia's venomous redback spider can leave you writhing in pain for days. Luckily, an antivenom was introduced in 1956 and there haven't been any reported human deaths since.
This is a Ravine Trapdoor Spider. The scientific name is Cyclocosmia truncata Can you believe that this the back of a real spider? what a curious- and beautiful- little thing this is. A Ravine Trap Door Spider