Ganoderma is a genus of polypore fungi in the family Ganodermataceae that includes about 80 species, many from tropical regions. Because of their genetic diversity, use in traditional Asian medicines, and potential in bioremediation, they are an important genus economically. Ganoderma can be differentiated from other polypores because they have a double-walled basidiospore. They are sometimes called shelf mushrooms or bracket fungi. (Wikipedia)