Amanita phalloides is SO NUTRITIOUS that eating a single bite is enough to FEED YOU FOR THE REST OF YOUR LIFE, which, in practical terms, is about 6-8 hours on average.
(this is the death cap mushroom, which has a 50% case fatality rate, please do not eat.)
The amatoxin contained in the Amanita phalloides completely inhibits your cells' ability to make new RNA, resulting in apoptosis of virtually every cell in your body.
Survival rate with advanced treatment is still only ~50%.
The amatoxins are remarkably dangerous:
They're water-soluble, freeze-resistant, heat-resistant, and present in every tissue of the fungus.
You can die from just putting them in the same basket with edible mushrooms (spores contain the amatoxin), cooking in water that has come in contact with them.
Only the fruiting bodies are really exposed to big vertebrate consumers, so my guess is that it doesn't need to offer aposematic warning, because eating the mushroom portion just decreases spore production.
I think there's more survival advantage in killing grubs/worms? Not sure.
