Phylogenetic position of the ectomycorrhizal basidiomycete Tricholoma dulciolens in relation to species of Tricholoma that produce “matsutake” mushrooms

• The phylogenetic position of Tricholoma dulciolens relative to matsutake species had been unknown.
• T. dulciolens is phylogenetically independent from Tricholoma matsutake and its allied species.
• The specimens from Abies alba forests in Spain are related to T. dulciolens.
• Based on rDNA ITS sequence data, T. dulciolens appears to exist in North America.

Tricholoma dulciolens is an ectomycorrhizal basidiomycete that produces “matsutake”-like mushrooms in association with Picea abies in Fennoscandia. The phylogenetic position of T. dulciolens relative to matsutake species is, however, unknown. In the present study, we demonstrated that T. dulciolens is phylogenetically independent from T. matsutake and its allied species. In addition, herbarium specimens identified as T. caligatum from Abies alba forests in Spain were phylogenetically related to but distinct from T. dulciolens. Based on ribosomal internal transcribed spacer DNA sequence data, T. dulciolens appears to exist in North America, as well. This is the first phylogeny of T. dulciolens in Fennoscandia and its related species in southern Europe.