The Polyporaceae are a family of poroid fungi belonging to the Basidiomycota. The flesh of their fruit bodies varies from soft to very tough. Most members of this family have their hymenium in vertical pores on the underside of the caps, but some of them have gills or gill-like structures. Many species are brackets, but others have a definite stipe – for example, Polyporus badius.

Cerioporus squamosus aka Polyporus squamosus is a basidiomycete bracket fungus, with common names including dryad's saddle and pheasant's back mushroom. It has a widespread distribution, being found in North America, Australia, Asia, and Europe, where it causes a white rot in the heartwood of living and dead hardwood trees. The name "dryad's saddle" refers to creatures in Greek mythology called dryads who could conceivably sit and rest on this mushroom, whereas the pheasant's back analogy derives from the pattern of colors on the bracket matching that of a pheasant's back.