Specific spider species, such as funnel-web spiders and black widows, possess venomous bites that can cause severe neurotoxic effects and medical emergencies in humans.
The retrieved papers provide strong, specific evidence that certain spider groups (such as Latrodectus, Steatoda, and Atrax) possess potent neurotoxic venoms capable of causing significant clinical symptoms or danger to humans. No papers contradict this empirical fact.