Colacogloea fennica sp. nov. (OM 22483). A. Basidiome. B. Three-septate basidium with four sterigmata, note colacosomes in hyphae bearing the basidium but not in the basidium. C. Basidiole. D. Cluster of conidiophores and conidia, note colacosomes in hyphae but not in conidiophores. E. Conidia. F. Basidiospores. G, H. Host–parasite interface, Pa = parasite cell, Ho = host cell, arrowheads indicate some positions of colacosomes. Scale bars: A = 1 cm; B–G = 10 μm.