Russula brevipes
A group of white mushrooms emerging from the ground
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Russulales
Family: Russulaceae
Genus: Russula
Species:
R. brevipes
Binomial name
Russula brevipes
Peck (1890)
Synonyms[2]
  • Russula brevipes var. acrior Shaffer (1964)[1]
  • Russula brevipes var. megaspora Shaffer (1964)[1]
Russula brevipes
View the Mycomorphbox template that generates the following list
Gills on hymenium
Cap is flat or infundibuliform
Hymenium is decurrent
Stipe is bare
Spore print is white
Ecology is mycorrhizal
Edibility is edible

Russula brevipes is a species of mushroom commonly known as the short-stemmed russula or the stubby brittlegill. It is widespread in North America, and was reported from Pakistan in 2006. The fungus grows in a mycorrhizal association with trees from several genera, including fir, spruce, Douglas-fir, and hemlock. Fruit bodies are white and large, with convex to funnel-shaped caps measuring 7–30 cm (3–12 in) wide set atop a thick stipe up to 8 cm (3 in) long. The gills on the cap underside are closely spaced and sometimes have a faint bluish tint. Spores are roughly spherical, and have a network-like surface dotted with warts.

The mushrooms of Russula brevipes often develop under masses of conifer needles or leaves of broadleaved trees, and fruit from summer to autumn. Forms of the mushroom that develop a bluish band at the top of the stipe are sometimes referred to as variety acrior. Although edible, Russula brevipes mushrooms have a bland or bitter flavor. They become more palatable once parasitized by the ascomycete fungus Hypomyces lactifluorum, a bright orange mold that covers the fruit body and transforms them into lobster mushrooms.

Taxonomy

Russula brevipes was initially described by American mycologist Charles Horton Peck in 1890, from specimens collected in Quogue, New York.[3] It is classified in the subsection Lactaroideae, a grouping of similar Russula species characterized by having whitish to pale yellow fruit bodies, compact and hard flesh, abundant lamellulae (short gills), and the absence of clamp connections. Other related Russula species with a similar range of spore ornamentation heights include Russula delica, R. romagnesiana, and R. pseudodelica.[1]

There has been considerable confusion in the literature over the naming of Russula brevipes. Some early 20th-century American mycologists referred to it as Russula delica, although that fungus was described from Europe by Elias Fries with a description not accurately matching the North American counterparts. Fries's concept of R. delica included: a white fruit body that did not change color; a smooth, shiny cap; and thin, widely spaced gills. To add to the confusion, Rolf Singer and later Robert Kühner and Henri Romagnesi described other species they named Russula delica. Robert Shaffer summarized the taxonomic conundrum in 1964:

Russula delica is a species that everybody knows, so to speak, but the evidence indicates that R. delica sensu Fries (1838) is not R. delica sensu Singer (1938), which in turn is not R. delica sensu Kühner and Romagnesi (1953)… It is best to use R. brevipes for the North American collections which most authors but not Kühner and Romagnesi (1953), call R. delica. The name, R. brevipes, is attached to a type collection, has a reasonably explicit original description, and provides a stable point about which a species concept can be formed.[1]

Shaffer defined the Russula brevipes varieties acrior and megaspora in 1964 from Californian specimens. The former is characterized by a greenish-blue band that forms at the top of the stipe, while the latter variety has large spores.[1] The nomenclatural database Index Fungorum does not consider these varieties to have independent taxonomical significance.[2] In a 2012 publication, mycologist Mike Davis and colleagues suggest that western North American Russula brevipes comprise a complex of at least four distinct species.[4] According to MycoBank, the European species Russula chloroides is synonymous with R. brevipes,[5] although Index Fungorum and other sources consider them distinct species.

The specific epithet brevipes is derived from the Latin words brevis "short" and pes "foot", hence "short-footed".[6] Common names used to refer to the mushroom include short-stemmed russula,[7] short-stalked white russula,[8] and stubby brittlegill.[9]

Description

Closeup of a white mushroom, showing a bluish-green band of color at the intersection of the gills and stipe.
A greenish band can develop at the top of the stipe.

Fully grown, the cap can range from 7 to 30 cm (3 to 12 in) in diameter, whitish to dull-yellow, and is funnel-shaped with a central depression. The gills are narrow and thin, decurrent in attachment, nearly white when young but becoming pale yellow to buff with age, and sometimes forked near the stipe. The stipe is 3–8 cm long and 2.5–4 cm thick. It is initially white but develops yellowish-brownish discolorations with age.[10] The mushroom sometimes develops a pale green band at the top of the stipe.[11] The spore print is white to light cream.[10]

Spores of R. brevipes are egg-shaped to more or less spherical, and measure 7.5–10 by 6.5–8.5 µm;[9] they have a partially reticulate (network-like) surface dotted with warts measuring up to 1 µm high.[4] The cap cuticle is arranged in the form of a cutis (characterized by hyphae that run parallel to the cap surface) comprising interwoven hyphae with rounded tips. There are no cystidia on the cap (pileocystidia).[12]

The variant R. brevipes var. acrior Shaffer has a subtle green shading at the stipe apex and on the gills.[10] R. brevipes var. megaspora has spores measuring 9–14 by 8–12 µm.[1]

Similar species

Russula delica is one of several R. brevipes look-alikes

The subalpine waxy cap (Hygrophorus subalpinus) is somewhat similar in appearance to R. brevipes but lacks its brittle flesh, and it has a sticky, glutinous cap.[13] The Pacific Northwest species Russula cascadensis also resembles R. brevipes, but has an acrid taste and smaller fruit bodies.[14] Another lookalike, R. vesicatoria, has gills that often fork near the stipe attachment.[15] R. angustispora is quite similar to R. brevipes, but has narrower spores measuring 6.5–8.5 by 4.5–5 µm, and it does not have the pale greenish band that sometimes develops in the latter species.[11] The European look-alike R. delica is widely distributed, although rarer in the northern regions of the continent. Similar to R. brevipes in overall morphology, it has somewhat larger spores (9–12 by 7–8.5 µm) with a surface ornamentation featuring prominent warts interconnected by a zebra-like patterns of ridges.[8] The milk-cap mushroom Lactifluus piperatus can be distinguished from R. brevipes by the production of latex when the mushroom tissue is cut or injured.[16]

Distribution and habitat

It is a common ectomycorrhizal fungus associated with several hosts across temperate forest ecosystems. Typical hosts include trees in the genera Abies, Picea, Pseudotsuga, and Tsuga.[17] The fungus has been reported in Pakistan's Himalayan moist temperate forests associated with Pinus wallichiana.[18] Fruit bodies grow singly or in groups; fruiting season occurs from summer to autumn.[9] In western North America, where the mushroom is quite common, it is encountered most frequently in late autumn.[19] The mushrooms are usually found as "shrumps"—low, partially emerged mounds on the forest floor,[20] and have often been partially consumed by mammals such as rodents or deer.[21]

Studies have demonstrated that geographically separated R. brevipes populations (globally and continentally) develop significant genetic differentiation, suggesting that gene flow between these populations is small.[21] In contrast, there was little genetic differentiation observed between populations sampled from a smaller area (less than approximately 1000 meters).[22] R. brevipes is one of several Russula species that associates with the myco-heterotrophic orchid Limodorum abortivum.[23]

Edibility

"Although attractive when clean and crisp, this harmless, prolific mushroom is constantly maligned because it mimics prized edibles such as the white matsutake and forms promising "shrumps" like those of the king bolete and chanterelle."

David Arora[20]

Russula brevipes is a non-descript edible species that tends to assume the flavors of meats and sauces it is cooked with.[13] It is one of several Russula species harvested in the wild from Mexico's Izta-Popo Zoquiapan National Park and sold in local markets in nearby Ozumba.[24] The mushrooms are suitable for pickling due to their crisp texture.[25]

Fruit bodies are commonly parasitized by the ascomycete Hypomyces lactifluorum, transforming them into an edible known as a lobster mushroom. In this form, the surface of the fruit body develops into a hard, thin crust dotted with minute pimples, and the gills are reduced to blunt ridges.[10] The flesh of the mushroom—normally brittle and crumbly—becomes compacted and less breakable.[26] Mycologist David Arora wrote in his book Mushrooms Demystified that R. brevipes is "edible, but better kicked than picked".[27]

Bioactive compounds

Sesquiterpene lactones are a diverse group of biologically active compounds that are being investigated for their antiinflammatory and antitumor activities.[28][29] Some of these compounds have been isolated and chemically characterized from Russula brevipes: russulactarorufin, lactarorufin-A, and 24-ethyl-cholesta-7,22E-diene-3β,5α,6β-triol.[30]

See also

References

  1. ^ a b c d e f Shaffer Robert L. (1964). "The subsection Lactariodeae of Russula". Mycologia. 56 (2): 202–31. doi:10.2307/3756537. JSTOR 3756537.
  2. ^ a b "GSD Species Synonymy: Russula brevipes Peck". Species Fungorum. CAB International. Retrieved 2014-01-23.
  3. ^ Peck CH. (1890). "Report of the Botanist (1889)" (PDF). Annual Report on the New York State Museum of Natural History. 43: 20.
  4. ^ a b Davis RM, Sommer R, Menge JA (2012). Field Guide to Mushrooms of Western North America. Berkeley, California: University of California Press. pp. 105–6. ISBN 978-0-520-95360-4.
  5. ^ "Russula brevipes Peck, Annual Report on the New York State Museum of Natural History 43: 66, t. 2:5-8 (1890)". MycoBank. International Mycological Association. Retrieved 2014-03-17.
  6. ^ Simpson DP. (1979). Cassell's Latin Dictionary (5 ed.). London: Cassell. p. 883. ISBN 978-0-304-52257-6.
  7. ^ Ostry ME, O'Brien JG, Anderson NA (2011). Field Guide to Common Macrofungi in Eastern Forests and Their Ecosystem Functions. Government Printing Office. p. 71. ISBN 978-0-16-088611-9.
  8. ^ a b Courtecuisse R. (1999). Mushrooms of Britain and Europe. Collins Wildlife Trust Guides. London, UK: HarperCollins. pp. 698, 701. ISBN 978-0-00-220012-7.
  9. ^ a b c McKnight KH. (1987). A Field Guide to Mushrooms: North America. Houghton Mifflin Harcourt. p. 318. ISBN 978-0-395-91090-0.
  10. ^ a b c d Arora D. (1986). Mushrooms Demystified. Berkeley, California: Ten Speed Press. pp. 87–8. ISBN 978-0-89815-169-5.
  11. ^ a b Roody WC. (2003). Mushrooms of West Virginia and the Central Appalachians. Lexington, Kentucky: University Press of Kentucky. p. 217. ISBN 0-8131-9039-8.
  12. ^ Kuo M. (March 2009). "Russula brevipes". MushroomExpert.com. Retrieved 2014-06-23.
  13. ^ a b Ammirati JF, McKenny M, Stuntz DE (1987). The New Savory Wild Mushroom. Seattle, Washington: University of Washington Press. p. 68. ISBN 978-0-295-96480-5.
  14. ^ Phillips R. "Russula brevipes". Rogers Mushrooms. Retrieved 2014-03-15.
  15. ^ Miller HR, Miller OK (2006). North American Mushrooms: A Field Guide to Edible and Inedible Fungi. Guilford, Connecticut: Falcon Guide. p. 76. ISBN 978-0-7627-3109-1.
  16. ^ Binion D, Stephenson SL, Roody WC, Burdsall HH Jr, Vasilyeva LN, Miller OK Jr (2008). Macrofungi Associated with Oaks of Eastern North America. West Virginia: West Virginia University Press. p. 243. ISBN 978-1933202365.
  17. ^ Kernaghan G, Currah RS, Bayer S (1997). "Russulaceous ectomycorrhizae of Abies lasiocarpa and Picea engelmannii". Canadian Journal of Botany. 75 (11): 1843–50. doi:10.1139/b97-896.
  18. ^ Niazi AR, Iqbal SH, Khalid AN (2006). "Biodiversity of mushrooms and ectomycorrhizas. 1. Russula brevipes Peck., and its ectomycorrhiza – A new record from Himalayan moist temperate forests of Pakistan" (PDF). Pakistan Journal of Botany. 38 (4): 1271–7.
  19. ^ Wood M, Stevens F. "Russula brevipes". California Fungi. MykoWeb. Retrieved 2014-03-19.
  20. ^ a b Arora D. (1991). All the Rain Promises and More. Berkeley: Ten Speed Press. p. 27. ISBN 978-0898153880.
  21. ^ a b Bergemann SE, Miller SL (2002). "Size, distribution, and persistence of genets in local populations of the late-stage ectomycorrhizal basidiomycete, Russula brevipes". New Phytologist. 156 (2): 313–30. doi:10.1046/j.1469-8137.2002.00507.x. JSTOR 1514022. PMID 33873278.
  22. ^ Bergemann SE, Douhan GW, Garbelotto M, Miller SL (2006). "No evidence of population structure across three isolated subpopulations of Russula brevipes in an oak/pine woodland". New Phytologist. 170 (1): 177–84. doi:10.1111/j.1469-8137.2006.01654.x. PMID 16539614. Open access icon
  23. ^ Girlanda M, Selosse MA, Cafasso D, Brilli F, Delfine S, Fabbian R, Ghignone S, Pinelli P, Segreto R, Loreto F, Cozzolino S, Perotto S (2006). "Inefficient photosynthesis in the Mediterranean orchid Limodorum abortivum is mirrored by specific association to ectomycorrhizal Russulaceae". Molecular Ecology. 15 (2): 491–504. doi:10.1111/j.1365-294X.2005.02770.x. PMID 16448415. S2CID 40474597.
  24. ^ Dugan FM. (2011). Conspectus of World Ethnomycology. St. Paul, Minnesota: American Phytopathological Society. p. 78. ISBN 978-0-89054-395-5.
  25. ^ Orr DB, Orr RT (1979). Mushrooms of Western North America. Berkeley, California: University of California Press. p. 186. ISBN 978-0-520-03656-7.
  26. ^ Spahr DL. (2009). Edible and Medicinal Mushrooms of New England and Eastern Canada. North Atlantic Books. p. 151. ISBN 978-1-55643-795-3.
  27. ^ Thiers, Harry D.; Arora, David (September 1980). "Mushrooms Demystified". Mycologia. 72 (5): 1054. doi:10.2307/3759750. ISSN 0027-5514.
  28. ^ Ghantous A, Gali-Muhtasib H, Vuorela H, Saliba NA, Darwiche N (2010). "What made sesquiterpene lactones reach cancer clinical trials?". Drug Discovery Today. 15 (15–16): 668–78. doi:10.1016/j.drudis.2010.06.002. PMID 20541036.
  29. ^ Merfort I. (2011). "Perspectives on sesquiterpene lactones in inflammation and cancer". Current Drug Targets. 12 (11): 1560–73. doi:10.2174/138945011798109437. PMID 21561425.
  30. ^ Suri OP, Shah R, Satti NK, Suri KA (1997). "Russulactarorufin, a lactarane skeleton sesquiterpene from Russula brevipes". Phytochemistry. 45 (7): 1453–5. Bibcode:1997PChem..45.1453S. doi:10.1016/S0031-9422(97)00121-0.
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