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Cordyceps

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Cordyceps
Cordyceps militaris
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Ascomycota
Class: Sordariomycetes
Order: Hypocreales
Family: Cordycipitaceae
Genus: Cordyceps
Fr. (1818)
Type species
Cordyceps militaris
(L.) Fr. (1818)

Cordyceps /ˈkɔːrdɪsɛps/ is a genus of ascomycete fungi (sac fungi) that includes about 750 species worldwide, 200 of these species are parasitic. Diverse variants of cordyceps have had more than 1,500 years of use in Chinese medicine.[1] Most Cordyceps species are endoparasitoids, parasitic mainly on insects and other arthropods (they are thus entomopathogenic fungi); a few are parasitic on other fungi.[2]

The generic name Cordyceps is derived from the ancient Greek κορδύλη kordýlē, meaning "club", and the Latin -ceps, meaning "-headed".[3] The genus has a worldwide distribution, with most of the known species[4] being from Asia (Nepal, China, Japan, Bhutan, Korea, Vietnam, and Thailand).

Taxonomy

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There are two recognized subgenera:[5]

  • Cordyceps subgen. Cordyceps Fr. 1818[6]
  • Cordyceps subgen. Cordylia Tul. & C. Tul. 1865[7]

Cordyceps sensu stricto are the teleomorphs of a number of anamorphic, entomopathogenic fungus "genera" such as Beauveria (Cordyceps bassiana), Septofusidium, and Lecanicillium.[8]

Splits

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Cordyceps subgen. Epichloe was at one time a subgenus, but is now regarded as a separate genus, Epichloë.[5]

Cordyceps subgen. Ophiocordyceps was at one time a subgenus defined by morphology. Nuclear DNA sampling done in 2007 shows that members, including "C. sinensis" and "C. unilateralis", as well as some others not placed in the subgenus, were distantly related to most of the remainder of species then placed in Cordyceps (e.g. the type species C. militaris). As a result, it became its own genus, absorbing new members.[8][9]

The 2007 study also peeled off Metacordyceps (anamorph Metarhizium, Pochonia) and Elaphocordyceps. A number of species remain unclearly assigned and provisionally retained in Cordyceps sensu lato.[8]

Species

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A wasp parasitized by an entomopathogenic species of Cordyceps

The following species are recognised in the genus Cordyceps:[10]

Biology

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When Cordyceps attacks a host, the mycelium invades and eventually replaces the host tissue, while the elongated fruit body (ascocarp) may be cylindrical, branched, or of complex shape. The ascocarp bears many small, flask-shaped perithecia containing asci. These, in turn, contain thread-like ascospores, which usually break into fragments and are presumably infective.[11]

Research

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Cordycepin

Polysaccharide components and the nucleoside cordycepin isolated from C. militaris are under basic research, but more advanced clinical research has been limited and too low in quality to identify any therapeutic potential of cordyceps components.[12]

Uses

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Along with Ophiocordyceps, Cordyceps has long been used in traditional Chinese medicine in the belief it can be used to treat diseases.[13] There is no strong scientific evidence for such uses.[12]

Cultural representations

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Cordyceps is represented culturally as a deadly threat to the human race, its parasitism powerful enough to result in global calamity. The video game series The Last of Us (2013–present) and its television adaptation present Cordyceps as a parasite of humans.[14][15] The result is a zombie apocalypse and the collapse of human civilization. Scientific American notes that some species in the genus "are indeed body snatchers–they have been making real zombies for millions of years", though of ants or tarantulas, not of humans.[14] The Last of Us proceeds from the premise that a new species of Cordyceps manages to jump between species of host, just as diseases like influenza have done. Its human hosts initially become violent "infected" beings, before turning into blind zombie "clickers", complete with fungal "fruiting bodies sprouting from their faces".[14] In an additional detail that reflects Cordyceps biology, "clickers" then seek out a dark place in which to die and release the fungal spores, enabling the parasite to complete its life cycle.[14] Scientific American comments that by combining a plausible mechanism with effective artistic design, the series gains "both scientific rigor and beauty".[14] In similar vein, Cordyceps causes a pandemic that wipes out most of humanity in Mike Carey's 2014 postapocalyptic novel The Girl with All the Gifts and its 2016 film adaptation.[16] In this case, an infected person becomes a "hungry", a zombie thirsting for blood. In the fiction, Dr. Caldwell explains that the human-infecting fungus is a mutated form of Ophiocordyceps unilateralis (a group of species now split off from Cordyceps) which alters the behaviour of infected insects. The children of infected mothers, however, become "hybrids" with antibodies protecting them against the fungus.[16]

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See also

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References

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Wikimedia Commons has media related to Cordyceps.
Wikispecies has information related to Cordyceps.
  1. ^ Buenz, E. J.; B. A. Bauer; Osmundson, T. W. & Motley, T. J. (2005). "The traditional Chinese medicine Cordyceps sinensis and its effects on apoptotic homeostasis". Journal of Ethnopharmacology. 96 (1–2): 19–29. doi:10.1016/j.jep.2004.09.029. PMID 15588646.
  2. ^ Nikoh, N (April 2000). "Interkingdom host jumping underground: phylogenetic analysis of entomoparasitic fungus of the genus cordyceps". Mol Biol Evol. 17 (4): 629–38. doi:10.1093/oxfordjournals.molbev.a026341. PMID 10742053.
  3. ^ "Cordyceps". www.merriam-webster.com. Retrieved 22 August 2023.
  4. ^ Sung, Gi-Ho; Nigel L. Hywel-Jones; Jae-Mo Sung; J. Jennifer Luangsa-ard; Bhushan Shrestha & Joseph W. Spatafora (2007). "Phylogenetic classification of Cordyceps and the clavicipitaceous fungi". Stud Mycol. 57 (1): 5–59. doi:10.3114/sim.2007.57.01. PMC 2104736. PMID 18490993.
  5. ^ a b "Cordyceps". Index Fungorum. Retrieved 4 September 2019.
  6. ^ Elias Magnus Fries, Observ. mycol. (Havniae) 2: 316 (cancellans) (1818)
  7. ^ Edmond Tulasne & Charles Tulasne, Select. fung. carpol. (Paris) 3: 20 (1865)
  8. ^ a b c Sung, GH; Hywel-Jones, NL; Sung, JM; Luangsa-Ard, JJ; Shrestha, B; Spatafora, JW (2007). "Phylogenetic classification of Cordyceps and the clavicipitaceous fungi". Studies in Mycology. 57: 5–59. doi:10.3114/sim.2007.57.01. PMC 2104736. PMID 18490993.
  9. ^ Holliday, John; Cleaver, Matt (2008). "Medicinal Value of the Caterpillar Fungi Species of the Genus Cordyceps (Fr.) Link (Ascomycetes). A Review" (PDF). International Journal of Medicinal Mushrooms. 10 (3). New York: Begell House: 219–234. doi:10.1615/IntJMedMushr.v10.i3.30. ISSN 1521-9437. Archived from the original (PDF) on 22 February 2012. Retrieved 10 March 2009.
  10. ^ "Index Fungorum - Search Page". www.indexfungorum.org. Retrieved 6 November 2024.
  11. ^ Shrestha, Bhushan; Han, Sang-Kuk; Sung, Jae-Mo; Sung, Gi-Ho (2012). "Fruiting Body Formation of Cordyceps militaris from Multi-Ascospore Isolates and Their Single Ascospore Progeny Strains". Mycobiology. 40 (2): 100–106. doi:10.5941/MYCO.2012.40.2.100. ISSN 1229-8093. PMC 3408298. PMID 22870051.
  12. ^ a b "Cordyceps". Drugs.com. 12 July 2023. Retrieved 15 September 2023.
  13. ^ "Chinese Medicine Specimen Database". libproject.hkbu.edu.hk. Retrieved 6 March 2023.
  14. ^ a b c d e Hill, Kyle (25 June 2013). "The Fungus that Reduced Humanity to The Last of Us". Scientific American. Retrieved 4 May 2021.
  15. ^ D'Addario, Daniel (10 January 2023). "'The Last of Us,' From 'Chernobyl's' Craig Mazin, Is a Promising, Moving Zombie Saga: TV Review". Variety. Retrieved 15 February 2023.
  16. ^ a b Bachman, Mara (12 April 2020). "The Girl With All The Gifts: Fungal Infection & Hungries Explained". ScreenRant. Retrieved 23 October 2023.
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