This research revealed that what was thought to be a single poisonous mushroom species in Japan (Kakishimeji) is actually four different species. Only one of these species contains significant levels of the toxin that causes stomach problems. This discovery helps explain why people in some regions can eat these mushrooms safely while others get sick. Impacts on everyday life: – Improved food safety through better identification of poisonous mushrooms – More accurate mushroom identification guides for foragers and consumers – Better understanding of which specific mushroom species are safe to eat – Reduced risk of mushroom poisoning through proper species identification – Enhanced knowledge for mushroom cultivation and commercial use