XVI International Botanical Congess

Quercus dominated forests of Costa Rica and Colombia support a broad assortment of both saprobic and ectomycorrhizal macrofungi, Agaricales in particular. The 13 species of Quercus in Costa Rica and Colombia form obligate ectomycorrhizal associations with a large proportion of these fungi and are found generally above 1500 m elevation. Ectomycorrhizal-forming agarics of the Boletaceae, Russulaceae, Cortinariaceae, and Amanitaceae are most common with lesser representatives in the Tricholomataceae, Entolomataceae, and Hygrophoraceae. The saprobic agarics are mostly members of the Tricholomataceae. Generic affinities of these montane agarics appear to lie with the temperate zones, whereas the non-montane agarics have neotropical, lowland affinities.