A TAXONOMIC STUDY OF THE GENUS TRICHOLOMA (AGARICALES) IN THE GREAT LAKES REGION

This is a taxonomic treatment of the mushroom genus Tricholoma (Agaricales) in the Great Lakes Region. The genus, a member of the family Tricholomataceae, has the following combination of features that distinguish it from other genera in the family: sinuate lamellar attachment; smooth, inamyloid spores that are white in deposit; parallel lamellar trama; and terrestrial fruiting habit.; Forty-six species and three varieties are reported. Complete descriptions are provided for the macroscopic and microscopic features of each taxon. Line drawings of spores and if present, hymenial cystidia, are provided for each taxon. Twenty-three species are illustrated with black and white photographs of fresh carpophores. Eight species are described as new and given provisional names; one variety is unnamed. Three species are reported for the first time from North America and five are reported for the first time from the Great Lakes Region.; Four subgenera are recognized and are in agreement with those recognized by Rolf Singer. The sectional classification of subgenus Tricholoma, is emended to include five sections instead of the three that are recognized by Singer.; Characters most useful in identifying or delimiting species are coloration of the entire carpophore; whether the pileus is viscid or dry; type of vestures on the pileus surface; presence or absence of a veil; size and shape of spores; presence or absence of cheilocystidia; presence or absence of clamp connections; and presence or absence of a pseudoparenchymatous subcutis.; Species of Tricholoma form ectomycorrhizae with forest trees and occur in both hardwood and coniferous forests in the Great Lakes Region. No experimental work was done to establish exact associations but information is provided giving suspected fungus-tree associations based on field observations. The fruiting season for Tricholoma begins in late August and continues until the time of continued frosts in late October.