Except for a handful of larger species, microscopic examination is always required to identify ascomycetes. Staining is often necessary to make hyaline tissues and spores visible - the question is what stain to use: as a rule of thumb: if it has asci, use Melzer's Iodine; other hyaline structures can be stained with Congo Red. Anamorphic fungi generally stain well in Cotton Blue, although dematiaceous hyphomycetes generally need no staining.