What genus includes the Sydney funnel-web spider?

The genus that includes the Sydney funnel-web spider is Atrax.

The species is Atrax robustus, a mygalomorph spider native to eastern Australia and usually found within roughly 100 kilometers of Sydney. Octavius Pickard-Cambridge formally described it in 1877 and established the genus name Atrax. The species name robustus is Latin for strong or sturdy.

Sydney funnel-webs build silk-lined burrows with trip-lines around the entrance. When insects or other small animals disturb those lines, the spider rushes out and delivers venom. Males wander more widely during the warmer months while searching for mates, and they are often responsible for medically significant encounters.

A common mix-up is treating every Australian funnel-web as Atrax robustus. The name Sydney funnel-web is also shared loosely with some related Hadronyche species, while Atrax contains several species. The medically important Sydney species is specifically Atrax robustus.