Lemon Drops growing from a wood fence.
Lemon Drops Bisporella citrina is one of the names of a very small mushroom produced by a fungus that lives in dead deciduous trees. The mushroom takes the form of a yellow disc no more than 3mm in diameter, usually smaller. The mushrooms are produced in clusters of dozens to hundreds, appearing at a distance like a uniform scum. Only by getting very close can you see the wonderful detail of the myriad individual fruiting bodies. Other common names include "lemon disco" (it must be an incomplete translation from a European common name) and "yellow fairy cups." They belong to the group of mushrooms called "cup fungi;" larger species in the group can be cup, bowl, or goblet shaped. Another small cup fungus covered earlier is the eylash cup, which grows on wood which is further decayed.