Omphalotus olivascens

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Omphalotus olivascens
Omphalotus olivascens 125218.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Omphalotaceae
Genus: Omphalotus
Species:
O. olivascens
Binomial name
Omphalotus olivascens
Omphalotus olivascens
Information icon.svg
Gills icon.png Gills on hymenium
Infundibuliform cap icon.svg Cap is infundibuliform
Decurrent gills icon2.svg Hymenium is decurrent
Bare stipe icon.svg Stipe is bare
Transparent spore print icon.svg
Spore print is yellow
Saprotrophic fungus.svgEcology is saprotrophic
Mycomorphbox Poison.pngEdibility is poisonous

Omphalotus olivascens, commonly known as the western jack-o'-lantern mushroom, [1] is an orange to brown-colored gilled poisonous mushroom endemic to the North American west coast. It has several lookalikes including Cantharellus cibarius .

Contents

Taxonomy

The fungus was described as new to science in 1976 by American mycologists Howard E. Bigelow, Orson K. Miller Jr., and Harry D. Thiers. [2] A subspecies with blue flesh, O. olivascens var. indigo, was described growing on live oak in Baja California, Mexico. [3]

Description

The cap is 4–18 cm (1.6–7.1 in) wide. The stalks are 4–15 cm (1.6–5.9 in) long and 1–4 cm (0.39–1.57 in) wide. The spores are white to pale yellow. [4]

Similar species

To an untrained eye, O. olivascens appears similar to Cantharellus cibarius , [1] but the jack-o'-lantern mushroom has true, blade-like [5] gills (rather than ridges) and it can have olive coloration that chanterelles lack; also, Omphalotus species are saprotrophic, grow directly on wood, and are bioluminescent. [6]

Several Omphalotus species with similar bioluminescent properties occur worldwide, all of which are presumed poisonous. The best known are the North American jack o'lantern mushroom ( O. olearius ) and the tsukiyotake ( O. japonicus (Kawam.) Kirchm. & O.K. Mill. (formerly known as Lampteromyces japonicus (Kawam.) Sing.), found in Japan and eastern Asia. Molecular analysis shows the jack-o'-lantern to be most closely related to the ghost fungus O. nidiformis, [7] the colours and shades of which most closely resemble O. olivascens. [8] Additionally, O. illudens is similar. [9]

Gymnopilus junonius is another similar-looking species. [4]

Distribution and habitat

It is endemic to the North American west coast, [1] namely the California Floristic Province.[ citation needed ]

Ecology

A saprobe or parasite, O. olivascens is usually found on oak or Eucalyptus , [9] rarely on other hosts.

Omphalotus species cause a white rot by breaking down lignin in their tree hosts. [7]

Toxicity

The jack o'lantern mushroom is poisonous; while not lethal, consuming this mushroom leads to very severe cramps, vomiting, and diarrhea. [6]

The toxic ingredient of many species of Omphalotus is a sesquiterpene compound known as illudin  S. [10] This, along with illudin M, have been identified in O. nidiformis. The two illudins are common to the genus Omphalotus and not found in any other basidiomycete mushroom. [11]

See also

References

  1. 1 2 3 Arora, David (1986) [1979]. Mushrooms Demystified: A Comprehensive Guide to the Fleshy Fungi (2nd ed.). Berkeley, CA: Ten Speed Press. p. 147. ISBN   978-0-89815-170-1.
  2. Bigelow HE, Miller OK Jr, Thiers HD (1976). "A new species of Omphalotus". Mycotaxon. 3 (3): 363–372.
  3. Moreno G, Esteve-Raventós F, Pöder R, Ayala N (1993). "Omphalotus olivascens var. indigo, var. nov. from Baja California (Mexico)". Mycotaxon. 48: 217–22.
  4. 1 2 Davis, R. Michael; Sommer, Robert; Menge, John A. (2012). Field Guide to Mushrooms of Western North America. Berkeley: University of California Press. pp. 143–144. ISBN   978-0-520-95360-4. OCLC   797915861.
  5. Meuninck, Jim (2017). Foraging Mushrooms Oregon: Finding, Identifying, and Preparing Edible Wild Mushrooms. Falcon Guides. p. 4. ISBN   978-1-4930-2669-2.
  6. 1 2 Wood, Michael & Stevens, Fred. "Omphalotus olivascens". California Fungi. Retrieved 2011-03-25.
  7. 1 2 Kirchmair M, Morandell S, Stolz D, Pöder R (2004). "Phylogeny of the genus Omphalotus based on nuclear ribosomal DNA-sequences". Mycologia. 96 (6): 1253–1260. doi:10.2307/3762142. JSTOR   3762142. PMID   21148949.
  8. Miller OK. Jr. (1994). "Observations on the genus Omphalotus in Australia". Mycologia Helvetica. 6 (2): 91–100.
  9. 1 2 Audubon (2023). Mushrooms of North America. Knopf. pp. 476–477. ISBN   978-0-593-31998-7.
  10. Benjamin DR (1995). Mushrooms: Poisons and Panaceas — A Handbook for Naturalists, Mycologists and Physicians. New York: WH Freeman and Company. pp. 366–67. ISBN   0-7167-2600-9.
  11. Kirchmair, Martin (1999). "Identification of illudins in Omphalotus nidiformis and Omphalotus olivascens var. indigo by column liquid chromatography–atmospheric pressure chemical ionization tandem mass spectrometry". Journal of Chromatography A. 832 (1–2): 247–52. doi:10.1016/s0021-9673(98)00892-9. ISSN   0021-9673. PMID   10070774.