''Ophiocordyceps sinensis'' (

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

''Cordyceps sinensis''), known colloquially as caterpillar fungus, is an entomopathogenic fungus (a fungus that grows on insects) in the family

Ophiocordycipitaceae Ophiocordycipitaceae is a family (biology), family of parasite, parasitic fungus, fungi in the phylum Ascomycota, class Sordariomycetes. It was created in 2007 to resolve the paraphyly of Calvicipitaceae. It was updated in 2020. Genera As accept ...

. It is mainly found in the meadows above on the

Tibetan Plateau The Tibetan Plateau, also known as the Qinghai–Tibet Plateau or Qingzang Plateau, is a vast elevated plateau located at the intersection of Central Asia, Central, South Asia, South, and East Asia. Geographically, it is located to the north of H ...

Tibet Tibet (; ''Böd''; ), or Greater Tibet, is a region in the western part of East Asia, covering much of the Tibetan Plateau and spanning about . It is the homeland of the Tibetan people. Also resident on the plateau are other ethnic groups s ...

and the Himalayan regions of

Bhutan Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia, in the Eastern Himalayas between China to the north and northwest and India to the south and southeast. With a population of over 727,145 and a territory of , ...

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

, and

Nepal Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia. It is mainly situated in the Himalayas, but also includes parts of the Indo-Gangetic Plain. It borders the Tibet Autonomous Region of China Ch ...

. It parasitizes larvae of ghost moths and produces a fruiting body which is valued in traditional

Chinese medicine Traditional Chinese medicine (TCM) is an alternative medical practice drawn from traditional medicine in China. A large share of its claims are pseudoscientific, with the majority of treatments having no robust evidence of effectiveness or ...

as an

aphrodisiac An aphrodisiac is a substance that increases libido, sexual desire, sexual attraction, sexual pleasure, or sexual behavior. These substances range from a variety of plants, spices, and foods to synthetic chemicals. Natural aphrodisiacs, such as ...

. However, naturally harvested fruiting bodies often contain high amounts of arsenic and other heavy metals, making them potentially toxic. As a result, their sale has been strictly regulated by China's

State Administration for Market Regulation The State Administration for Market Regulation (SAMR; ) is a ministerial-level agency directly under the State Council of the People's Republic of China responsible for market supervision and management. SAMR was established in 2018. It is China ...

since 2016. ''O. sinensis'' parasitizes the larvae of moths within the family

Hepialidae The Hepialidae are a family of insects in the lepidopteran order. Moths of this family are often referred to as swift moths or ghost moths. Taxonomy and systematics The Hepialidae constitute by far the most diverse group of the infraorder Exop ...

, specifically genera found on the

and in the Himalayas, between elevations of . The fungus germinates in the living larva, kills and mummifies it, and then a dark brown stalk-like fruiting body which is a few centimeters long emerges from the corpse and stands upright. ''O. sinensis'' is classified as a medicinal mushroom, and its use has a long history in

traditional Chinese medicine Traditional Chinese medicine (TCM) is an alternative medicine, alternative medical practice drawn from traditional medicine in China. A large share of its claims are pseudoscientific, with the majority of treatments having no robust evidence ...

as well as in

traditional Tibetan medicine Traditional Tibetan medicine or Sowa Rigpa is the Tibetan medical system developed in the 8th century under King Trisong Detsen that incorporated the best international medical practices of that time.Claude Arpi, ''Glimpses on the Tibet History' ...

. It is marketed for various health benefits but lacks sufficient

scientific evidence Scientific evidence is evidence that serves to either support or counter a scientific theory or hypothesis, although scientists also use evidence in other ways, such as when applying theories to practical problems. "Discussions about empirical ev ...

for safety or effectiveness, and quality can vary due to inconsistent processing and labeling. The hand-collected, intact fungus-caterpillar body is valued by herbalists as medicine, and because of its cost, its use is also a status symbol. The fruiting bodies of the fungus are not cultivated commercially outside of China,Hsieh, C., et al., A Systematic Review of the Mysterious Caterpillar Fungus Ophiocordyceps sinensis in Dong-ChongXiaCao and Related Bioactive Ingredients. Vol. 3. 2013. 16–32. but the mycelium form can be cultivated in vitro. Overharvesting and

overexploitation Overexploitation, also called overharvesting or ecological overshoot, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to ...

have led to the classification of ''O. sinensis'' as an endangered species in China. Additional research needs to be carried out in order to understand its morphology and growth habits for conservation and optimum utilization.

Taxonomic history and systematics

Morphological features

''Ophiocordyceps sinensis'' consists of two parts, a fungal endo

sclerotium A sclerotium (; : sclerotia () is a compact mass of hardened fungal mycelium containing food reserves. One role of sclerotia is to survive environmental extremes. In some higher fungi such as ergot, sclerotia become detached and remain dormant u ...

(within the caterpillar) and stroma. The stroma is the upper fungal part and is dark brown or black, but can be a yellow color when fresh, and longer than the caterpillar itself, usually 4–10 cm. It grows singly from the larval head, and is clavate, sublanceolate or fusiform, and distinct from the stipe (stalk). The stipe is slender, glabrous, and longitudinally furrowed or ridged. The fertile part of the stroma is the head. The head is granular because of the

ostiole An ''ostiole'' is a small hole or opening through which algae or fungi release their mature spores. The word is a diminutive of wikt:ostium, "ostium", "opening". The term is also used in higher plants, for example to denote the opening of the ...

s of the embedded

perithecia An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascoc ...

. The perithecia are ordinally arranged and ovoid. The asci are cylindrical or slightly tapering at both ends, and may be straight or curved, with a capitate and hemispheroid apex, and may be two to four spored. Similarly, ascospores are hyaline, filiform, multiseptate at a length of 5–12 μm and subattenuated on both sides. Perithecial, ascus and ascospore characters in the fruiting bodies are the key identification characteristics of ''O. sinensis''. ''Ophiocordyceps'' ( Petch) Kobayasi species produce whole ascospores and do not separate into part spores. This is different from other ''Cordyceps'' species, which produce either immersed or superficial perithecia perpendicular to stromal surface, and the ascospores at maturity are disarticulated into part spores. Generally ''Cordyceps'' species possess brightly colored and fleshy stromata, but ''O. sinensis'' has dark pigments and tough to pliant stromata, a typical characteristic feature of most of the ''Ophiocordyceps'' species.

Developments in classification

The species was first described scientifically by Miles Berkeley in 1843 as ''Sphaeria sinensis'';

Pier Andrea Saccardo Pier Andrea Saccardo (23 April 1845 in Treviso, Province of Treviso, Treviso – 12 February 1920 in Padua, Italy, Padua) was an Italian botany, botanist and mycology, mycologist. His multi-volume ''Sylloge Fungorum'' was one of the first attempt ...

transferred the species to the genus '' Cordyceps'' in 1878. The fungus was known as ''Cordyceps sinensis'' until 2007, when

molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

analysis was used to amend the

classification Classification is the activity of assigning objects to some pre-existing classes or categories. This is distinct from the task of establishing the classes themselves (for example through cluster analysis). Examples include diagnostic tests, identif ...

of the Cordycipitaceae and the

Clavicipitaceae The Clavicipitaceae are a family (biology), family of fungi within the order Hypocreales. A 2008 estimate placed 43 genus, genera in the family, but a study in 2020 has increased this number to 50. Phylogeny Molecular phylogeny, phylogenetic ana ...

, resulting in the naming of a new family

and the transfer of several ''Cordyceps'' species including ''C. sinensis'' to the genus '' Ophiocordyceps''.

Common names

In Tibet, it is known as yartsa gunbu, (, "summer grass winter worm"). The name was first recorded in the 15th century by the Tibetan doctor Zurkhar Namnyi Dorje. In colloquial Tibetan yartsa gunbu is often shortened to simply "bu" or "yartsa". The Tibetan name is transliterated in Nepali as यार्चागुन्बू, यार्चागुन्बा, ''yarshagumba'', ''yarchagumba'' or ''yarsagumba''. The transliteration in Bhutan is . In India, it is known as ''keera jhar'', ''keeda jadi'', ''keeda ghas'' or in Nepali, Hindi and Garhwali. It is known in Chinese as (冬蟲夏草), meaning "winter worm, summer grass", which is a literal translation of the original Tibetan name. In traditional Chinese medicine, its name is often abbreviated as ''chong cao'' (蟲草 "insect plant"), a name that also applies to other ''Cordyceps'' species, such as ''C. militaris''. In Japanese, it is known by the Japanese reading of the characters for the Chinese name, . Strangely, sometimes in Chinese English-language texts ''Cordyceps sinensis'' is referred to as ''aweto'', which is the

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

name for '' Ophiocordyceps robertsii'', a species from south-eastern

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. The English term "vegetable caterpillar" is a misnomer, as no plant is involved. "Caterpillar fungus" is a preferred term.

Synonyms

Since the 1980s, 22 species in 13 genera have been attributed to the anamorph (asexually reproducing mold-like form) of ''O. sinensis''. Additional synonyms for the teleomorph are '' Cordyceps nepalensis'' and ''C. multiaxialis''. They have similar morphological characteristics to ''O. sinensis'', also had almost identical or identical ITS sequences and its presumed anamorph, ''H. sinensis''.

Ecology and life cycle

The

caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder ...

s prone to infection by ''O. sinensis'' generally live underground in alpine grass and shrub-lands on the

and the

Himalayas The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...

at an altitude between . The fungus is reported from the northern range of Nepal, Bhutan, and also from the northern states of India, apart from northern Yunnan, eastern Qinghai, eastern Tibet, western Sichuan, southwestern Gansu provinces. Fifty-seven taxa from several genera (37 '' Thitarodes'', 1 '' Bipectilus'', 1 ''

Endoclita ''Endoclita'' is a genus of moths of the family Hepialidae. There are 60 described species found in eastern and southeast Asia and the Indian subcontinent. Species *'' Endoclita aboe'' – India *'' Endoclita absurdus'' – China *'' Endoclita ...

'', 1 '' Gazoryctra'', 3 '' Pharmacis'', and 14 others not correctly identified to genus) are recognized as potential hosts of ''O. sinensis''. The stalk-like dark brown to black fruiting body (or mushroom) grows out of the head of the dead caterpillar and emerges from the soil in alpine meadows by early spring. During late summer, the fruiting body disperses spores. The caterpillars, which live underground feeding on roots, are most vulnerable to the fungus after shedding their skin, during late summer. In late autumn, chemicals on the skin of the caterpillar interact with the fungal spores and release the fungal

mycelia Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are fo ...

, which then infects the caterpillar. The infected larvae tend to remain underground vertical to the soil surface with their heads up. After invading a host larva, the fungus ramifies throughout the host and eventually kills it. Gradually the host larvae become rigid because of the production of fungal sclerotia. Fungal sclerotia are multihyphal structures that can remain dormant and then germinate to produce spores. After overwintering, the fungus ruptures the host body, forming the fruiting body, a sexual sporulating structure (a perithecial stroma) from the larval head that is connected to the sclerotia in the dead larva below ground and grows upward to emerge from the soil to complete the cycle. The slow growing ''O. sinensis'' grows at a comparatively low temperature, i.e., below 21 °C. Temperature requirements and growth rates are crucial factors that distinguish ''O. sinensis'' from other similar fungi.

Climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

is suspected to be negatively affecting the mountain organism.

Use in traditional Asian medicines

The use of caterpillar fungus as

folk medicine Traditional medicine (also known as indigenous medicine or folk medicine) refers to the knowledge, skills, and practices rooted in the cultural beliefs of various societies, especially Indigenous groups, used for maintaining health and treatin ...

apparently originated in Tibet and Nepal. So far the oldest known text documenting its use was written in the late 15th century by the Tibetan doctor Zurkhar Nyamnyi Dorje (Wylie: ) 439–1475 in his text: ("Instructions on a Myriad of Medicines"), where he describes its use as an aphrodisiac. The first mention of ''Ophiocordyceps sinensis'' in traditional Chinese medicine was in Wang Ang’s 1694 compendium of materia medica, ''Ben Cao Bei Yao''. In the 18th century it was listed in Wu Yiluo's ''Ben cao cong xin'' ("New compilation of materia medica"). The ethno-mycological knowledge on caterpillar fungus among the Nepalese people is documented. The entire fungus-caterpillar combination is hand-collected for medicinal use. In traditional Chinese medicine, it is regarded as having an excellent balance of

yin and yang Originating in Chinese philosophy, yin and yang (, ), also yinyang or yin-yang, is the concept of opposite cosmic principles or forces that interact, interconnect, and perpetuate each other. Yin and yang can be thought of as complementary an ...

as it is considered to be composed of both an animal and a vegetable. Wild-collected "cordyceps" is not always true ''O. sinensis'', even when the location and the host insect matches. This has resulted in the description of new species such as ''Cordyceps liangshanensis'' ( Liangshan, China; many Nepali "cordyceps" are also incorrectly identified to be this species, and no new names for them have been proposed yet) and ''Samsoniella hepiali'' (Qinghai, China). Despite not being the same species when examined using a modern method, these material is largely used in the same way in traditional medicine. There are also "cordyceps" species that are traditionally known to be different from ''O. sinensis'' but nevertheless thought to be have a similar tonifying action. China is home to at least 299 species of "cordyceps" in this broadest sense. It is marketed for various health benefits but lacks sufficient

for safety or effectiveness, and quality can vary due to inconsistent processing and labeling.

Secondary metabolites

A 2008 source reports that ''O. sinensis'' contains cordycepin, an

adenosine Adenosine (symbol A) is an organic compound that occurs widely in nature in the form of diverse derivatives. The molecule consists of an adenine attached to a ribose via a β-N9- glycosidic bond. Adenosine is one of the four nucleoside build ...

derivative originally discovered in ''C. militaris''. However, this study uses store-bought material labeled as ''O. sinensis'' without any molecular confirmation that it is indeed the species. A more in-depth 2017 study, which fully characterized the biosynthetic machinery for cordycepin, found that ''O. sinensis'' does not produce cordycepin. This discrepancy underscores the importance of correctly identifying "cordyceps" species.

Economics

In rural

, ''yartsa gunbu'' has become the most important source of cash income. The fungi contributed 40% of the annual cash income to local households and 8.5% to the GDP in 2004. Prices have increased continuously, especially since the late 1990s. In 2008, one kilogram traded for US$3,000 (lowest quality) to over US$18,000 (best quality, largest larvae). The annual production on the Tibetan Plateau was estimated in 2009 at 80–175 tons. The Himalayan ''Ophiocordyceps'' production might not exceed a few tons. In 2004 the value of a kilogram of caterpillars was estimated at 30,000 to 60,000 Nepali rupees in Nepal, and about Rs 100,000 in India. In 2011, the value of a kilogram of caterpillars was estimated at 350,000 to 450,000 Nepali rupees in Nepal. A 2012 BBC article indicated that in north Indian villages a single fungus was worth Rs 150 (about £2 or $3), which is more than the daily wage of a manual labourer. In 2012, a pound of top-quality yartsa had reached retail prices of $50,000. VM 5591 Lanzhou Dong chong xia cao

The price of ''Ophiocordyceps sinensis'' is reported to have increased dramatically on the

, about 900% between 1998 and 2008, an annual average of over 20% (after inflation). However, the value of large caterpillar fungus has increased more dramatically than small ''Cordyceps'', regarded as lower quality. In the

Kingdom of Bhutan Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia, in the Eastern Himalayas between China to the north and northwest and India to the south and southeast. With a population of over 727,145 and a territory of , ...

, ''Ophiocordyceps sinensis'' is recently also being harvested. The Bhutanese "cordyceps" has been molecularly confirmed to be ''O. sinensis'', with its quality shown to be equal to the Tibetan one.

Impacts of wild collection

Societal impact

Because of its high value, inter-village conflicts over access to its grassland habitats has become a headache for the local governing bodies and in several cases people were killed. In November 2011, a court in Nepal convicted 19 villagers over the murder of a group of farmers during a fight over the prized aphrodisiac fungus. Seven farmers were killed in the remote northern district of Manang in June 2009 after going to forage for Yarchagumba. Its value gave it a role in the

Nepalese Civil War The Nepalese Civil War was a protracted armed conflict that took place in the then Kingdom of Nepal from 1996 to 2006. It saw countrywide fighting between the Kingdom rulers and the Communist Party of Nepal (Maoist), with the latter making ...

, as the Nepalese Maoists and government forces fought for control of the lucrative export trade during the June–July harvest season. Collecting ''yarchagumba'' in Nepal had only been legalised in 2001, and now demand is highest in countries such as China, Thailand, Vietnam, Korea and Japan. By 2002, the 'herb' was valued at R 105,000 ($1,435) per kilogram, allowing the government to charge a royalty of R 20,000 ($280) per kilogram.

Ecological impact

The search for ''Ophiocordyceps sinensis'' is often perceived to threaten the environment of the

where it grows. While it has been collected for centuries and is still common in such areas, current collection rates are much higher than in historical times. In India, fuelwood cutting by ''Ophiocordyceps sinensis'' collectors near the treeline is reported to be depleting populations of tree species such as Himalayan birch ''

Betula utilis ''Betula utilis'', the Himalayan birch (''bhojpatra'', ''bhūrjá''), is a deciduous tree native to the Western Himalayas, growing at elevations up to . The Latin specific epithet ''utilis'' means "useful", and refers to the many uses of the dif ...

''.

Cultivation

Mycelia

Cultivated ''O. sinensis'' mycelium is an alternative to wild-harvested ''O. sinensis'', and producers claim it may offer improved consistency. Artificial culture of ''O. sinensis'' is typically by growth of pure mycelia in liquid culture (in China) or on grains (in the West). ''Ophiocordyceps sinensis'' is now cultivated on an industrial scale for their use in traditional Chinese medicine. However, no one has succeeded so far in rearing the fungus by infecting cultivated caterpillars; all products derived from cultured ''Ophiocordyceps'' are derived from mycelia grown on grains or in liquids. In Chinese, the mycelia is used as a powder called zh, s=发酵冬虫夏草菌粉, l=fermented winter-worm-summer-grass powder. However, the same term is also informally used for the powdered mycelia of the related '' Samsoniella hepiali'', also a pathogen of ghost-moths. In

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

, according to the statistics of the Ministry of Agriculture and Rural Development, the production of cultivated "cordyceps" () in

in 2022 reached about 1,000 tons, an increase of five times compared to 2017. The selling price of fresh ''O. sinensis'' ranges from 10-20 million VND/kg, while dried ''O. sinensis'' ranges from 100-200 million VND/kg. Therefore, the economic value of cultivated "cordyceps" in

is estimated to be around 10,000 billion VND/year. In the period 2017-2022, the production of cultivated "cordyceps" has grown at an average rate of 40%/year.

Fruiting body

A fruiting body with a mature perithecium was first grown in laboratory conditions in China in 1983, using a growth media. By 2014, it was possible to obtain a mature fruiting body with a rice-based growth media in a low-altitude location. However, such amorphous culture media do not generate a product with the traditional presentation of "worm and grass". Inoculation of caterpillars leading to a fully mature fruiting body was reported in 1991. This led to an early form of cultivation: caterpillars were artificially inoculated with the fungus, then placed into the natural habitat to induce the generation of the fruiting body. This increased the yield of the product, but was still subject to climate variations. In 2016, it became possible to mature the inoculated insects in a controlled environment. ''O. sinensis'' cultivated this way has been commercialized in China. Rearing of the caterpillars intended for inoculation can be affected by parasitic nematodes and other entomopathogenic fungi in the environment. Maturation of inoculated caterpillars can be disrupted by rodents eating them as food. Growth media may become a food source for ''Sciara'' flies.

Cultivated alternatives

A number of related

Hypocreales The Hypocreales are an order of fungi within the class Sordariomycetes. In 2008, it was estimated that it contained some 237 genera, and 2647 species in seven families. Since then, a considerable number of further taxa have been identified, in ...

fungi have been collected in the field and found to be more amenable to cultivation. These fungi contain many of the same secondary metabolites as those in ''O. sinensis'' and Asian sources claim a similar spectrum of pharmacological effects. Some have also found use in traditional medicine as a substitute: * '' Cordyceps militaris'' fruiting body is cultivated in China, Vietnam, Taiwan, and Indonesia. The golden-colored fruiting body is eaten as an inexpensive mushroom. * '' Samsoniella hepiali'' mycelia is cultivated in China. It is used in two "Jinshuibao" products found in the Pharmacopoeia of the People's Republic of China and more than 260 healthcare products in China, with a total market worth of approximately 10 billion RMB. * '' Paecilomyces tenuipes'' contains acetoxyscirpenediol and ergosterol peroxide. It is cultivated in Korea. In some traditional-medicine contexts, it is acceptable to include the above alternatives in the term "cordyceps" or . Li ''et al.'' (2023) (in Chinese) provides a more detailed overview of the cultivation of ''Cordyceps'' sensu lato globally.

References

External links

* *
Yartsa Gunbu (Cordyceps sinensis) in TibetAn Electronic Monograph of Cordyceps and Related Fungi

information from Drugs.com
Cordyceps sinensis (Berk.) Sacc.
Medicinal Plant Images Database (School of Chinese Medicine, Hong Kong Baptist University)
Tibet’s Golden "Worm"
August 2012

National Geographic (magazine) ''National Geographic'' (formerly ''The National Geographic Magazine'', sometimes branded as ''Nat Geo'') is an American monthly magazine published by National Geographic Partners. The magazine was founded in 1888 as a scholarly journal, nine ...

{{Authority control Fungi described in 1843 Fungi of Asia Ophiocordycipitaceae Medicinal fungi Fungi used in traditional Chinese medicine Taxa named by Miles Joseph Berkeley Parasitic fungi Fungus species Fungi in cultivation