About Hydnum rufescens Pers.
Hydnum rufescens Pers., commonly called the terracotta hedgehog, is an edible basidiomycete in the family Hydnaceae. It is part of the small group of mushrooms known as tooth fungi. Tooth fungi produce fruit bodies where the undersurface of the cap is covered in hymenophores that look like spines or teeth, rather than pores or gills.
This species is very similar to the more common hedgehog fungus Hydnum repandum, and was sometimes previously classified as a variety of that species. Several consistent differences between the two have been noted. H. rufescens has a russet cap instead of the beige cap of H. repandum, is smaller overall with a more regular shape and a central stipe, its spines are not decurrent, and its spores are slightly larger.
Both species grow on soil in European coniferous and deciduous forests. H. rufescens is reported to form ectomycorrhizae with Picea abies, Pinus sylvestris, Fagus sylvatica, and Quercus robur.
