Atrax robustus, commonly known as the Sydney funnel-web spider, is a highly venomous spider native to eastern Australia. It is easily recognized by its large size, dark coloration, and distinctive fangs that can penetrate human skin. These spiders are typically found in moist environments, such as gardens and forests, where they build silk-lined burrows. The venom of Atrax robustus contains a potent neurotoxin that can be dangerous to humans, causing severe symptoms if bitten. However, antivenom is available, and fatalities are rare due to effective medical treatment. These spiders are primarily active at night and are known for their aggressive behavior when threatened.