Cortinarius

C. violaceus

Cortinarius is a genus of mushrooms. It is suspected to be the largest genus of agarics, containing over 2000 different species and found worldwide.[1] A common feature among all species in the genus Cortinarius is that young specimens have a cortina (veil) between the cap and the stem, hence the name, meaning curtained. Most of the fibers of the cortina are ephemeral and will leave no trace once gone, except for limited remnants on the stem in some species. All have a rusty brown spore print. The common names cortinar and webcap refer to members of the genus. Due to dangerous toxicity of several species (such as Cortinarius orellanus) and the fact that it's difficult to distinguish between various species of the genus, non-expert consumption of mushrooms from the genus is discouraged.

Distinguishing features

The veil protects the gills in younger specimens and usually disappears leaving little to no trace of itself as the mushroom grows. The spores of a Cortinarius mushroom are rusty brown to brownish red in color. It is usually possible to identify a mushroom as being a member of the genus, but extremely difficult to positively identify the species as many of the species are nearly identical. All mushrooms in this genus form mycorrhizae.[2]

Many mushrooms in the genus—for example Cortinarius sanguineus and other species in section Dermocybe—are colourful and are often used for dyeing.

Toxicity

Several mushrooms in the genus Cortinarius are poisonous, mainly because they cause acute tubulointerstitial nephritis. Some are even lethal, such as Cortinarius rubellus and Cortinarius orellanus. Therefore, a common rule when it comes to mushrooms from this genus is that none of them should be eaten. However, some species—notably the giant of the genus, Cortinarius praestans and the gypsy mushroom (Cortinarius caperatus)—are edible and appreciated in several European countries.

The toxin in Cortinarius species, orellanine is easy to detect because it is fluorescent. It has been found in at least 34 Cortinariaceae.[3]

Classification

Molecular studies of members of the genus Rozites, including its most famous member R. caperata have shown them nested within Cortinarius and have been sunk into this genus.[4]

Some consider the subgenus Dermocybe to have generic status.[5]

Species

References

  1. ↑ Kirk PM, Cannon PF, Minter DW, Stalpers JA. (2008). Dictionary of the Fungi (10th ed.). Wallingford, UK: CAB International. p. 173. ISBN 978-0-85199-826-8.
  2. ↑ Singer R. (1986). The Agaricales in Modern Taxonomy (4th ed.). Königstein im Taunus, Germany: Koeltz Scientific Books. p. 441. ISBN 3-87429-254-1.
  3. ↑ Oubrahim H, Richard J-M , Cantin-Esnault D, Seigle-Murandi F, Trecourt F. (1997). "Novel methods for identification and quantification of the mushroom nephrotoxin orellanine. Thin-layer chromatography and electrophoresis screening of mushrooms with electron spin resonance determination of the toxin". Journal of Chromatography 758 (1): 145–57. doi:10.1016/S0021-9673(96)00695-4. PMID 9181972.
  4. ↑ Peintner U, Horak E, Meinhard M, Vilgalys R. (2002). "Rozites, Cuphocybe and Rapacea are taxonomic synonyms of Cortinarius: New combinations and new names". Mycotaxon 83: 447–51.
  5. ↑ Bougher, N. L. & J. M. Trappe (2002). "Dermocybe globuliformis: first report of a hypogeous species for the genus". Australasian Mycologist 21 (1): 1–3.

External links

Media related to Cortinarius at Wikimedia Commons

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