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

Abstract

Abstract

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