and what is its indicator vlaue?
They have been used as indicator species of healthy natural forests or old-growth forests in Europe.
Polypore
Polypores have been used as indicator species of healthy natural forests or old-growth forests in Europe. 
what kind of species is phellinus ellipsoideus? Polypore fungus in the family Hymenochaetaceae mention any one delimitations of the first term? Most of them have a poroid hymenium.
wiki:12128645
Polypore [SEP] Indicator value
Polypores have been used as indicator species of healthy natural forests or old-growth forests in Europe. They are good indicators of invertebrate diversity on dead wood and include many endangered species. Polypores make good indicators because they are relatively easy to find – many species produce conspicuous and long-lasting fruiting bodies – and because they can be identified in the field. The first indicator list of polypores widely used in forest inventories and conservation work was developed in northern Sweden in 1992 ("Steget före" method). "Steget före" list included six polypores in three value classes. In Finland, a list of 30 species for spruce-dominated forests was published in 1993 and widely adopted.