New species of Tricholoma in sections Genuina and Fucata from eastern North America

Six new species of Tricholoma (Fr.) Staude in sections Genuina ( Tricholoma amarissimum, , Tricholoma lutescentifolium, , Tricholoma pudorinum, , Tricholoma sapineum) ) and Fucata ( Tricholoma griseobrunneum, , Tricholoma pallidogriseum) ) are formally described from North America east of the Rocky Mountains based on their nrITS sequence, morphology, ecology, and distribution patterns. Those species are found in summer or fall in deciduous or coniferous forests. Descriptions of their morphological characters are provided, along with photographs of the basidiomata and their micromorphology. The new species are compared with similar species occurring in North America and Europe. Tricholoma felschii Ovrebo, Hughes & Halling, in section Fucata, , is here considered to represent three species, T. felschii s. str., Tricholoma subumbrinum A.H. Sm., and the newly described T. griseobrunneum. . Emended descriptions of the first two species are provided to accommodate the new concepts.