On a scale of pain inflicted by insects. This little baby ranked the highest for fastest most painful after-effects. Ranking quite a bit above even fire ants and the like
The most painful bite from an insect is from the bullet ant, appropriately named because the bite feels like being shot with a bullet. It's also described as "walking over flaming coals with a three inch rusty nail in your heel".

But yeah, tarantula wasps are horrid. Quite pretty though.