According to Decock & Stalpers (2006) the concept of P. medulla-panis used of e.g. Ryvarden & Gilbertson (1994) was broad and included two species in Europe. As defined by Decock & Stalpers (2006) P. medulla-panis is known only from Europe (ranging from Italy to Norway, eastward to Russia).
Perenniporia medulla-panis is wood decay polypore fungus found on dead hardwood, especially oak (Quercus). It is widespread, but considered rare in Europe and distributed in Europe north up to the limit of the Quercus range. The species is threatened by felling of host trees and removal of coarse woody debris.
Perenniporia medulla-panis is saprotrophic wood-inhabiting fungus growing on hardwood trees especially on Quercus, but it is also known from other trees, such as Alnus, Betula, Corylus, Fagus, Tilia, Fraxinus. It grows on stumps, coarse fallen trunks or on old living trees in trunk cavities in old oak forests or mixed forests with oaks. Fruit body is perennial, widely effused, resupinate, 2-20 mm thick, tough-corky. Pore surface white when fresh, later cream colour, the pores small and circular.
Stalpers, J.A., Decock C., 2006. Studies in Perenniporia: Polyporus unitus, Boletus medulla-panis, the Nomenclature of Perenniporia, Poria and Physisporus, and a Note on European Perenniporia with a Resupinate Basidiome. Taxon 55: 759-778.