Sydney funnel-web spiders are one of only two Australian funnel-web spiders known to have inflicted fatal bites on humans. Combine their toxicity with their aggression, and you've got a notorious spider.
They range in size from 1 to 3 inches, with the females being larger. The females spend their time in their silken, tubular burrow retreats, while the males spend the warmer months wandering about in search of a receptive female.
Back to their venom: it contains a substance known as atraxotoxin (good name for a rock band?), which is highly toxic to primates. We humans are therefore advised to steer clear of these spiders. The males seek out water, and are therefore often found floating in pools. But they have survive such conditions for 24-hours, and can still deliver a full envenomation bite if plucked from the water without care. Said the funnel-web spider to its bitten savior, "You knew what I was when you pulled me from the water."
Photo source: Tim Marshall