Translated from the Dutch mycological society:
Wednesday, November 26th, 2014
In the park surrounding Recreatieplas Twiske, close to Oostzaan, there was an extraordinary discovery. During a walk of two members of the mycological society a group of mushrooms was found. The flawless specimens stood out because of their subtle beauty and photos were made. After identification they turned out to be Agaricus subfloccosus, a very rare Red List species that is threatened with extinction.