Abstract The lichen Lecanora schistina (Nyl.) Arnold has two kinds of conidia: filiform microconidia and obpyriform macroconidia. Both appear mixed in the same conidioma, the former being much more abundant. Sometimes these conidiomata contain a third type of conidia (microconidia) belonging most probably to a lichenicolous coelomycete living in the conidiomata of the lichen.