Macropsalliota americana

Last updated
Macropsalliota americana
Leucoagaricus-Americanus1.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Agaricaceae
Genus: Macropsalliota
Species:
M. americana
Binomial name
Macropsalliota americana
(Peck) Kun L. Yang, Jia Y. Lin & Zhu L. Yang (2024)
Synonyms [1]
  • Agaricus americanus(Peck)
  • Lepiota americana(Peck) Sacc.
  • Lepiota bresadolaeSchulzer
  • Agaricus americanusPeck (1869)
  • Leucocoprinus americanus(Peck) Redhead (1979)
  • Leucocoprinus biornatussensu auct. brit., auct. eur. (2005)
  • Leucoagaricus americanus (Peck) Vellinga (2000)
Macropsalliota americana
Mycological characteristics
Gills icon.png Gills on hymenium
Flat cap icon.svgConvex cap icon.svg Cap is flat or convex
Free gills icon2.svg Hymenium is free
Ring stipe icon.svg Stipe has a ring
Transparent spore print icon.svg
Spore print is white
Saprotrophic fungus.svgEcology is saprotrophic
Mycomorphbox Caution.pngEdibility is not recommended

Macropsalliota americana, commonly known as the American parasol, [2] is the type species of the fungus genus Macropsalliota . It was formerly known as Leucoagaricus americanus. It is widely distributed in North America, mostly east of the Rocky Mountains. It is saprobic and grows on sawdust, wood chips, stumps, and the ground.

Contents

Taxonomy

The species was first described as Agaricus americanus by the American mycologist Charles Horton Peck in 1872 [3] and then reclassified as Lepiota americana in 1887 by the Italian mycologist Pier Andrea Saccardo. [4]

In 1979 it was reclassified as a Leucocoprinus americanus by the Canadian mycologist Scott A. Redhead [5] and then as Leucoagaricus americanus by the mycologist Else Vellinga in 2000. [6]

In 2024 the species was reclassified as Macropsalliotaamericana by the Chinese mycologists Kun L. Yang, Jia Y. Lin & Zhu L. Yang and became the type species of the newly created Macropsalliota genus. [7]

Description

The cap is oval in shape when immature, becoming convex to flat when fully grown, reaching up to 3–15 centimetres (1+14–6 in) wide. [8] The cap feels dry and smooth at the beginning, but gradually gets reddish to reddish brown scales. It is white in color but reddens with maturity or after being handled. [9] The gills are free from the stipe and lie close together. They appear white when young and are stained pinkish to maroon. The stipe is 7–14 cm long, often enlarged at or below the middle and tapering toward the base. It appears white at first, staining or aging pink or reddish brown. It feels smooth with its silky hairs. The membranous veil leaves a white double edged ring on the upper stipe that may disappear in age. [10]

The spores are white to cream in color and measure 8–10 x 6–7.5  μm. [1] The flesh is white throughout. It bruises yellow to orange when cut and develops red colouration when old or when dried. The flesh is thick and discolors when cut, bruised or damaged. [10]

It is reported to be edible, but not recommended for consumption because of possible confusion with toxic species like Chlorophyllum molybdites . [10]

Distribution and habitat

It is widely distributed in its native North America, [10] though more common east of the Rocky Mountains; it is saprobic, and grows on sawdust, on wood chips, on stumps, and on the ground. [9]

Edibility

The species is regarded as edible [5] though it is generally not recommended for inexperienced foragers due to the potential to confuse it with dangerously toxic species. [11] [12]


References

  1. 1 2 Wood, Michael; Fred Stevens. "California Fungi—Leucoagaricus americanus". Mykoweb. California Fungi.
  2. Arora, David (1986) [1979]. Mushrooms Demystified: A Comprehensive Guide to the Fleshy Fungi (2nd ed.). Berkeley, CA: Ten Speed Press. p. 301. ISBN   978-0-89815-170-1.
  3. Peck, Charles Horton (1870). "Report of the Botanist". Annual Report of the Regents of the University on the condition of the State Cabinet of Natural History, with catalogues of the same. 23: 71 via biodiversitylibrary.org.
  4. Saccardo, P. A. (1887). Sylloge fungorum omnium hucusque cognitorum. Vol. v.5 (1887). Patavii. p. 43.{{cite book}}: CS1 maint: location missing publisher (link)
  5. 1 2 Groves, J. Walton; Redhead, S. A. (1979). Edible and poisonous mushrooms of Canada (Rev. ed.). Ottawa: Research Branch, Agriculture Canada. ISBN   978-0-660-10136-1.
  6. Vellinga, Else C. (December 2000). "Notes on Lepiota and Leucoagaricus". Mycotaxon. 76: 433 via biodiversitylibrary.org.
  7. YANG, KUN L.; LIN, JIA Y.; LI, GUANG-MEI; LI, TAIHUI; YANG, ZHU L. (2024-12-11). "Rediscovering Leucoagaricus sinicus, with the recognition of Leucoagaricus and Leucocoprinus as separate genera, and two new genera in Agaricaceae (Basidiomycota)". Phytotaxa. 676 (3): 199–255. doi:10.11646/phytotaxa.676.3.1. ISSN   1179-3163.
  8. Audubon (2023). Mushrooms of North America. Knopf. p. 567. ISBN   978-0-593-31998-7.
  9. 1 2 Kuo, M. (2005, October). Leucoagaricus americanus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/leucoagaricus_americanus.html
  10. 1 2 3 4 Rogers Mushrooms. "Leucoagaricus americanus". Archived from the original on 2011-11-09.
  11. "The American Parasol: A Comprehensive Identification Guide - Mushroom Appreciation". www.mushroom-appreciation.com. 2023-11-27. Retrieved 2026-01-03.
  12. "Leucoagaricus americanus - Leucoagaricus americanus - Discover the Wild". discoverthewild. Retrieved 2026-01-03.