Jacobsson, S. & E. Larsson. Hygrophorus penarioides, a new species identified using morphology and ITS sequence data. Mycotaxon 99: 337–343. 2007.

ABSTRACT: Hygrophorus penarius sensu lato is a whitish, dry or only slightly viscid, rather robust mushroom forming ectomycorrhizae with Fagus sylvatica or Quercus spp. There are slight morphological differences between the Fagus and the Quercus forms. The taxonomy has been complicated. Both forms have been interpreted as Hygrophorus penarius. Based on ITS sequence data it is here shown that they ought to be looked upon as two distinct species. As no reliable name in the literature could be used that fits the species associated with Quercus it is here described as a new species, Hygrophorus penarioides.

KEYWORDS: Basidiomycotina, Agaricales, phylogeny