Leucocoprinus cretaceus

Leucocoprinus cretaceus is a species of mushroom producing fungus in the family Agaricaceae. It is likely tropical in origin although it was first documented in Europe where it was often found growing in greenhouses and bark beds. However many early observations conflate this species with the more common Leucocoprinus birnbaumii or Leucocoprinus cepistipes despite sharing only superficial similarities. This fungus is quite versatile even for a saprotroph and is often found growing in clusters on woodchips, sawdust and compost heaps as well as directly from the ground or on trees. It may also appear in plant pots and greenhouses in colder countries in which it is not well equipped to survive outside....read more on Wikipedia.