Armillaria sinapina is a species of mushroom in the family Physalacriaceae.
Description The brownish cap is wide and the white, fibrous stem is up to long. Both the flesh and spore print are whitish. The mycelium is bioluminescent.
Similar species Armillaria gallica and A. calvescens grow only on dead wood (usually hardwood) but may require microscopy to distinguish. A. gemina and A. ostoyae are also similar.
Habitat A plant pathogenic fungus, it causes Armillaria root disease, and has been found on a variety of tree hosts in Alaska.
See also List of Armillaria species List of bioluminescent fungi
References