Cup fungi are fungi (Ascomycota: family Pezizaceae) which produce a mushroom that tends to grow in the shape of a "cup". Spores are formed on the inner surface of this fruiting body (mushroom). The cup shape typically serves to focus raindrops into splashing spores out of the cup. Additionally, the curvature enables wind currents to blow the spores out in a different manner than in most agaric and boletes.
Cup fungi grow in peculiar shapes, frequently resembling cups or saucers. For example, the orange peel fungus (Aleuria aurantia), which looks just like a discarded orange rind. They may be vividly colored, like the scarlet cup, which is often one of the first signs of spring where it grows.
While most cup fungi are not poisonous, as with all mushroom hunting, one should never consume a mushroom without identifying it first.