QuickCheck: Are 'daddy longlegs' spiders the most venomous arachnid in existence?

Some species of harvestmen are very gregarious (CC BY-SA 3.0).

YOU’RE dusting your home of dust and cobwebs and scurrying off to a corner you catch a glimpse of a tiny-bodied, long-legged creature, almost invisible but terrifying.

It has been passed down through generations that daddy longlegs spiders are actually the most venomous arachnids in existence but in a cruel twist of fate, their jaws or fangs are not long or strong enough to cause harm to humans.