Stereum is type genus of the Stereaceae family of fungi, in the Russulales order. Until recently, the genus was classified in the Corticiaceae family, of the Corticiales order. However, it was given its own family as a result of the split-up of the Corticiales. Common names for species of this genus include leaf fungus, wax fungus, and shelf fungus. Fungi having a shape similar to a Stereum are said to have a stereoid shape. Stereum contains 27 species that have a widespread distribution.