distributed in North America, Europe, West Asia including eastern Anatolia and Iran, North Africa, and southern Africa. It has been introduced into Australia. It occurs in woods, lawns, gardens and hedgerows in autumn. This is a saprobic species. Toxicity Although it appears that some people can eat this mushroom without ill effects, it contains toxins which can cause serious gastric problems. It is indigestible and gives rise to symptoms of sweating, flushing, and severe stomach cramps. Of those who gather Agaricus-style mushrooms, about 50% of the cases of poisoning are from this species. On cooking, the smell becomes very noticeable, and this may deter people from eating it inadvertently. Related species Agaricus xanthodermus belongs to a group of related species (the "Xanthodermati") which likewise discolour bright yellow and have a phenolic smell. They include A. praeclaresquamosus (formerly A. placomyces) which has dark grey scales, A. moelleri, and A. pilatianus, which does not have a bulbous stem. Agaricus californicus is also similar in appearance. See also List of Agaricus species References Collins Gem Guide: Mushrooms and Toadstools, Stefan Buckzacki (1982). xanthodermus Fungi described in 1876 Fungi of Europe Fungi of North America Poisonous fungi