Reassessment of the generic limits for Hydnellum and Sarcodon (Thelephorales, Basidiomycota)

DNA sequences from the nuclear LSU and ITS regions were used for phylogenetic analyses of Thelephorales with a focus on the stipitate hydnoid genera and . Analyses showed that and are distinct genera but that the current division, based on basidioma texture, makes paraphyletic with respect to . In order to make genera monophyletic several species are moved from to and the following new combinations are made: , , , , , , , , , , , and . Basidiospore size seems to separate the genera in most cases. species have basidiospore lengths in the range 4.45-6.95 µm while the corresponding range for is 7.4-9 µm. deviates from this pattern with an average spore length around 6 µm. Neotropical species represent a separate evolutionary lineage.