The small and very delicate Pleated Inkcap (sometimes also referred to as the Fairy Parasol or the Japanese Umbrella) is a typical grassland fungus that usually appears after a period of heavy rain.
Dutch name : Plooirokje
German name : Scheibchen-Tintling
Latin name : Parasola plicatilis (previous Coprinus plicatilis)
A big thanks to [fc-user:797972] for the kindly nomination of this picture.