Pseudosperma sororium

Pseudosperma sororium
Scientific classification
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Inocybaceae
Genus: Pseudosperma
Species:
P. sororium
Binomial name
Pseudosperma sororium
(Kauffman) Matheny & Esteve-Rav
Synonyms

Inocybe sororia Kauffman

Pseudosperma sororium
Mycological characteristics
Gills on hymenium
Cap is conical or umbonate
Hymenium is adnate or free
Stipe has a cortina
Spore print is brown
Ecology is mycorrhizal
Edibility is poisonous

Pseudosperma sororium, commonly known as the corn-silk fiberhead, is a species of mushroom in the family Inocybaceae. It is poisonous, has a fibrillose cap, and grows under both hardwood and conifer trees.[1]

Taxonomy

Pseudosperma sororium was first described in 1924 by Calvin Henry Kauffman as Inocybe sororia.[2] It kept that name for a very long time. In 2020, Matheny et al. split the genus Inocybe into several other genera, including Pseudosperma. Inocybe sororia was renamed Pseudosperma sororium and became the type species of Pseudosperma.[3]

Description

The cap of Pseudosperma sororium is about 3.5-11 centimeters in diameter. It starts out conical, and becomes umbonate in age.[1] It is yellowish brown or straw-colored and very fibrillose.[4] When the mushroom is older, the cap begins to split. At this stage, it can resemble straw. The stipe is about 6-12 centimeters long and 1-2 centimeters wide, and has a slightly wider base.[1] A cortina is present.[4] The gills start out pale, becoming darker and eventually brownish in age. They can be sinuate, adnexed, adnate, or free.[5] The spore print is brownish.[1] This mushroom smells like green corn.[4]

Habitat and ecology

Pseudosperma sororium grows in forests,[5] where it is found under both hardwoods and conifers.[1] It fruits during fall and winter.[5]

Toxicity

Pseudosperma sororium is poisonous, containing the toxin muscarine.[5][6][1]

References

  1. ^ a b c d e f Siegel, Noah; Schwarz, Christian (September 1, 2024). Mushrooms of Cascadia: A Comprehensive Guide to Fungi of the Pacific Northwest. Humboldt County, CA: Backcountry Press. p. 162. ISBN 9781941624197.
  2. ^ "Inocybe sororia". MykoBank.
  3. ^ Bandini, Ditte; Oertel, Brend (October 15, 2020). "Three new species of the genus Pseudosperma (Inocybaceae)" (PDF). Czech Mycology.
  4. ^ a b c Trudell, Steve (October 25, 2022) [January 1, 2009]. Mushrooms of the Pacific Northwest (Revised ed.). Portland, OR: Timber Press. p. 208. ISBN 9781643260860.
  5. ^ a b c d Arora, David (1986) [1979]. Mushrooms demystified: a comprehensive guide to the fleshy fungi (2nd ed.). Berkeley: Ten Speed Press. ISBN 978-0-89815-169-5.
  6. ^ Stevens, Michael Wood & Fred. "California Fungi: Pseudosperma sororium". www.mykoweb.com. Retrieved 2025-10-28.