Well, not quite everything is venemous.
Of the
520 species of lizards none are venomous but you could get an infection from a bite from a Goanna or Perenti or lose your life to a crocodile.
Out of ~
170 species of snakes (including sea snakes) 100 are venomous, about 12 being extremely venomous. Some like the Eastern Tiger snake, Taipan, Eastern Brown Snake, Copperhead, Death Adder, and Yellow-Bellied sea snake are so venomous you could die from a bite in 1~2 hours if no treatment was administered.
Out of
2400 species of spider, less than 50 are harmful to humans...
There's probably only 5~6 that you should worry about as the others will just cause a painful bite.
The most dangerous and deadly is the Funnel Web, (the male is much smaller than the female but is much more deadly) followed by the Redback spider, Mouse Spiders and White tailed Spiders.
Other extremely deadly creatures include, Stonefish, Lion Fish, BlueBottles, Sea Wasps, Textile Cone, Blue Ringed Octopus, Box jellyfish, Saltwater Crocs, Fresh Water Crocs and many species of sharks (Grey Nurse, White Pointer, Tiger Shark, Hammerhead, Black Tipped Reef Shark, Blue Shark, Bronze Whaler, Bull Shark, etc) that would think nothing of having you for lunch!
But possibly the most dangerous animal in Aus would have to be this guy!
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