Hypomyces luteovirens (Fr.) Tul. Fruit body a white then olive-green to dark green mold which produces dark green perithecia that project as small pimples. The mold covers the gills and stalk of lactarius and russula mushrooms. Spores spindle-shaped, finely warted, transparent, 1-celled, 28-35 x 4.5-5.5µ. Habitat in woods on various species of russula and lactarius mushrooms. Common in wet weather wherever the host species are found, throughout many parts of North America. Season July-November. Not edible.