Rickenella fibula

Rickenella fibula or Omphalina fibula, and commonly known as the orange moss navel is a species of fungus belonging to the genus Rickenella. It is orange to yellow and occurs among moss, which is why it is sometimes called moss sentinel. The cap is quite small, with a diameter usually less than 1 cm. The stipe is relatively long. It has little odor or taste, and is regarded as nonpoisonous.

According to molecular analysis, the species is more closely related to certain polypores and crust fungi than other gilled mushrooms. A similar species is Rickenella swartzii.