There are several genera of funnel web spiders, but the most common ones in Australia are Atrax, Hadronyche, and Illawarra. They vary in size and color, usually black or brown, with shiny carapaces. The males are generally smaller and less robust than the females.

Scientists in Australia have discovered a spider that they've unironically nicknamed "Big Boy." This arachnid is a larger, more venomous version of the Sydney funnel web, known to be one of the world's deadliest spiders.