Leucocoprinus birnbaumii

Leucocoprinus birnbaumii, the yellow houseplant mushroom, previously known as Lepiota lutea, is a common fungus that grows in many house plants, generally occurring in warmer areas, or in greenhouses or potted plants.

Description
The main identifying feature is the bright yellow colour of the mushrooms. The cap (pileus) in the young fruit-bodies is usually taller than broad, though becoming convex, often with shallow radial grooves near the margin, with maturity. There is a ring left on the stipe.

Edibility
This fungus is not edible and may be poisonous.