Lyophyllum paelochroum

Description:

Lyophyllum paelochroum Clmenon (1982)many thanks to Irene Andersson ( www.swefungi.se/ ) for help with ID!These medium-sized to large, fleshy fungi appeared in the anomalously cool and wet summer of 2009 in noticeable numbers. They were fruiting throughout the summer within residential areas of Akademgorodok in small groups on soil areas with scarce grass, usually near birch (Betula pendula) . I had never seen these fungi before and was rather confused by the appearance of such large and conspicuous yet unknown species.They have the overall stature of a Tricholoma terreum, but their cap is smooth with fine innate fibrils and their gills slowly stain blue and then black when bruised. The spores are white in mass, smooth, nearly globose, 5-6 m in diameter.A relatively recent monograph on Macromycetes of South-Western Siberia (N. Perova, I. Gorbunova, 2001) lists two other species of Lyophyllum with black-staining reaction, L. infumatum and L. semitale, however, the former has large rhomboid spores and the latter is darker and is found in different habitats.