Two new species of Hydnum with ovoid basidiospores: H. ovoideisporum and H. vesterholtii

Two new species of Hydnum, characterized by slender Hydnum rufescens-like basidiomes and ovoid to broadly ellipsoid basidiospores, are described from the Iberian Peninsula based on morphological and ITS molecular data. Hydnum ovoideisporum is distinguished by pilei with deep orange tones and strong preference for calcareous soil. It is widespread in the Iberian-Mediterranean area. Hydnum vesterholtii is characterized by its ocher to light ocher pileus, and nearly all the collections were made in the Pyrenees. Both ovoid-spored species are monophyletic well supported groups in the maximum parsimony and Bayesian ITS phylogenies, while the remainder of the samples assigned to H. rufescens s.l. and having globose basidiospores split into six well supported clades. The need to typify the name Hydnum rufescens is discussed, and a provisional key is given for the European taxa of Hydnum.