Marasmius siccus

Marasmius siccus, or orange pinwheel,[1] is a small orange mushroom in the Marasmius genus, with a "beach umbrella"-shaped cap. The tough shiny bare stem is pale at the top but reddish brown below, and the gills are whitish. The stem is 3–7 centimetres (1.2–2.8 in) tall and the cap is 0.5–2.5 centimetres (0.20–0.98 in) wide.[2][3][4][5]

Marasmius siccus
2016-08-16 Marasmius siccus (Schwein.) Fr 714682.jpg
Scientific classification edit
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Marasmiaceae
Genus: Marasmius
M. siccus
Binomial name
Marasmius siccus

At a microscopic level, the club-shaped spores are very long and thin, being roughly 19 µm by 4 µm. The distinctive cheilocystidia are broadly club-shaped with finger-like protrusions at the far end. Such cells also sometimes occur in other related mushrooms and they are known as "broom cells of the siccus type".[4][5]

This mushroom is found in hardwood forests from the Rocky Mountains to the Appalachian Mountains[6] and also in northern Europe and Asia.[4][5]

Although nonpoisonous, they are too small to be considered worthwhile as food.[7]

A cluster of M. siccus
Gills and the stem, which lightens at the top


  1. ^ "Marasmius siccus". Indiana University. Retrieved 16 February 2015.
  2. ^ Kuo, Michael. "Marasmius siccus". MushroomExpert.Com. Retrieved 16 February 2015.
  3. ^ "Marasmius siccus". University of Arkansas. Retrieved 16 February 2015.
  4. ^ a b c Antonín, V.; Noordeloos, M. E. (2010). A monograph of marasmioid and collybioid fungi in Europe. Berchtesgaden, DE: IHW Verlag. p. 84. ISBN 978-3-930167-72-2.
  5. ^ a b c Knudsen, Thomas; Vesterholt, J., eds. (2018). Funga Nordica Agaricoid, boletoid, clavarioid, cyphelloid and gasteroid genera. Copenhagen: Nordsvamp. p. 360. ISBN 978-87-983961-3-0.
  6. ^ Kuo, Michael; Methven, Andy (2010). 100 Cool Mushrooms. Ann Arbor, MI: University of Michigan Press. p. 115. ISBN 978-0472034178.
  7. ^ Miller Jr., Orson K.; Miller, Hope H. (2006). North American Mushrooms: A Field Guide to Edible and Inedible Fungi. Guilford, CN: FalconGuide. p. 198. ISBN 978-0-7627-3109-1.