Ophiocordyceps 2

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Miranda McCleaf
Mycology
2 December 2013
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* Characteristics of the genus Ophiocordyceps
* Taxonomic specifications
* Life Cycle Characteristics
* Three Prominent Species* O. sinensis
* O. unilateralis
* O. nutans
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* Species are entomopathogenic fungi
* Often to species specific hosts
* Scientifically described by Tom Petch in 1931
* 140+ species defined
* Similar life history to Cordyceps
Fruiting bodies of Ophiocordyceps sp.
Fruiting bodies of Ophiocordyceps dipterigena
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* Division- Ascomycota
* Correspond to Anamorphic genera such as Hirsutella, Hymenostilbe,
Paraisaria, and Syngliocladium
* Family- Ophiocordycipitaceae
* Close relation to Cordyceps
Anamorph type – Hirsutella neovolkiana
Fruiting bodies of Cordyceps sp.
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* Targets specific insect host
* Co-evolution with life history traits of insect
* High investment in producing multiple sporulation events
* Increase the likelihood in infecting a new host
* Manipulates host to behave ‘zombie-like’ and locate a location
for optimal fungal growth
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* O. sinensis
* Parasitizes caterpillars of Ghost Moths
* O. unilateralis
* Parasitizes Carpenter Ants
* O. nutans
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Parasitizes Stinkbugs
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* Formally Cordyceps sinensis
* Native to Tibetan Plateau of Asia
* Parasitizes on larval individuals of the genus Thitarodes
* Traditionally called Summer-plant and Winter-worm
* Mistakenly nicknamed ‘vegetable caterpillar’
* Medicinal Value:
* Used to treat asthma and respiratory inflammation
* Used as an aphrodisiac
* May alleviate fatigue and symptoms associated with cancer
* High economic value
* Excessively harvested and in decline in natural populations
* Listed as an endangered species in China
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* Life Cycle: Parasitizes then Mummifies
* Anamorphic Hirsutella sinensis becomes telomorphic when it infects
the host
* Infected caterpillar is positioned 2-5cm below soil surface with
head facing upward
* Stroma grows from the head of the deceased caterpillar and
produces a fruiting body
* Characteristics:
* Ascospores are hyaline,
filiform and multiseptate
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* Formally Cordyceps unilateralis
* Native to Thailand
* Creates the ‘zombie ant’ extended phenotype
* Targets species specific Camponotus leonardi
* Ecological Interest:
* Unique parasite to host co-evolution
* Contributes to the study of microhabitat use
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* Life Cycle: Expresses extended phenotype
* Extended phenotype causes the ant to become displaced and clamp
onto the underside of a leaf
* The ant locks its mandibles and dies allowing the mycelium to fill the
body cavity
* Fruiting body emerges from the ants head and then releases ascospores
in bouts to infect a new individual
* Characteristics:
* Ascus is perithecium shaped
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* Formally Cordyceps nutans
* Native to Japan, Taiwan, China and New Guinea
* Targets several stinkbug species in Heteroptera
* Pest Management Implications:
* Stinkbugs cause agriculture and forest damage
* Invasive pest species
* Biological control agent instead of chemical control?
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* Ophiocordyceps belongs to the Division Ascomycota
* They share similar life histories to Cordyceps
* Belong to very species specific parasite- host interactions
* 140+ species
* Some are significant in economical, medicinal, ecological and
biological pest control uses
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*
Sung, G-H., Hywel-Jones, NL., Sung, J-M., Luangsa-ard, JJ., Shrestha, B., et al. (2007) Phylogenetic classification
of Cordyceps and the clavicipitaceous fungi. Studies in Mycology 57: 5–59.
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Sasaki, Fumito, Miyamoto, Toshizumi, Yamamoto, Aki, Tamai, Yutaka, and Yajima, Takashi. (2012) Relationship
between intraspecific variations and host insects of Ophiocordyceps nutans collected in Japan. Mycoscience 53(2):
85-91.
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Shresthaa, Bhushan, Zhangb, Weimin, Zhangc, Yongjie, and Liud, Xingzhong. (2010) What is the Chinese caterpillar
fungus Ophiocordyceps sinensis (Ophiocordycipitaceae)? Mycology: An International Journal on Fungal Biology 1(4):
228-236.
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Andersen, Sandra B., Gerritsma, Sylvia, Yusah, Kalsum M., Mayntz, David, Hywel‐Jones, Nigel L., Billen, Johan,
Boomsma, Jacobus J. and Hughes, David P. (2009) The Life of a Dead Ant: The Expression of an Adaptive Extended
Phenotype. The American Naturalist 174(3): 424-433.
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Sung, G-H., Hywel-Jones, NL., Sung, J-M., Luangsa-ard, JJ., Shrestha, B., et al. (2007) Phylogenetic classification
of Cordyceps and the clavicipitaceous fungi. Studies in Mycology 57: 5–59.
*
Kendrick, Bryce. (1985) The Fifth Kingdom. 3rd ed. Waterloo, Ont., Canada: Mycologue Publications. 66-67. Print.
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