Rhizomarasmius [SEP] parent taxon
Rhizomarasmius
Rhizomarasmius is a genus of fungi in the family Physalacriaceae, containing about five species. 
General.
The genus was created in 2000 by R. H. Petersen to accommodate two species then classified in Marasmius ("M. pyrrhocephalus" and "M. undatus"), but which do not belong there due to morphological grounds, including the nature of the cystidia and the way the mushrooms are rooted on a plant substrate. This analysis was backed up in 2006 by DNA comparisons done by Wilson and Desjardin.
Unlike most
Rhizomarasmius epidryas
Rhizomarasmius epidryas (syn. Marasmius epidryas or Mycetinis epidryas) is one of a group of mushrooms formerly in the genus "Marasmius". It grows amongst dwarf shrubs of the genus "Dryas" in arctic or high mountain environments.
Description.
The species can be described as follows: 
- The cap is brownish yellow and grows to about 1 cm in diameter.
- The gills are white and fairly distant, and broadly attached to the stem. The spore powder is white.