Hyphomycetes
   HOME

TheInfoList



OR:

Hyphomycetes are a
form classification Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of s ...
of
fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...
, part of what has often been referred to as fungi imperfecti, Deuteromycota, or
anamorph In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota: *Teleomorph: the sexual reproductive stage (morph), typically a fruiting body. *Anamorph: an ase ...
ic fungi. Hyphomycetes lack closed
fruit bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...
, and are often referred to as moulds (or molds). Most hyphomycetes are now assigned to the
Ascomycota Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...
, on the basis of genetic connections made by life-cycle studies or by
phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
analysis of
DNA sequence DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. Th ...
s; many remain unassigned phylogenetically. Although no longer considered a phylogenetically defined taxon, the prevalence of hyphomycete forms in nature, the built environment, and laboratories means that identification of members this group remains of practical importance.


Taxonomic and nomenclatural history

Because asexual forms of fungi usually occur separately from their sexual forms, when microscopic fungi began to be studied in the early 19th century, it was often unknown when two morphologically different forms were actually part of one species. The tendency for some organisms to apparently only have asexual forms, or for their sexual forms to be discovered long after the asexual forms, meant that an independent taxonomy was developed for asexual fungi. Near the beginning of the 20th century, when it became clearer that many asexual and sexual forms were related, the concept of 'form taxa' was developed. The independent taxonomy of asexual forms was regarded as artificial, not representative of evolutionary relationships, and intended to be practical for identification purposes. The taxonomy of the sexual states was considered the true classification. The result was that many fungal species ended up with two accepted Latin binomials, one for the asexual form (or anamorph) and the other for the sexual form (teleomorph). This dual nomenclature was only abandoned in January 2012, and the transition to a single name system, with one name representing all morphs of a fungus, is still incomplete.


Identification

Traditional identification of hyphomycetes was primarily based on microscopic
morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...
including:
conidia A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the ...
l morphology, especially septation, shape, size, colour and cell wall texture, the arrangement of conidia as they are borne on the conidiogenous cells (e.g. if they are solitary, in chains, or produced in slime), the type of conidiogenous cell (e.g. non-specialized or
hypha A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...
-like,
phialide The phialide ( ; el, phialis, diminutive of phiale, a broad, flat vessel) is a flask-shaped projection from the vesicle (dilated part of the top of conidiophore) of certain fungi. It projects from the mycelium without increasing in length unless ...
, annellide, or
sympodial Sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, also referred to a ...
), and other additional features such as the presence of sporodochia or
synnemata A synnema (plural ''synnemata'', also ''coremia''; derivation: "Threads together") is a large, erect reproductive structure borne by some fungi, bearing compact conidiophore A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamy ...
. For species growing in culture, or in environmental DNA studies, most identifications of Hyphomycetes are now done with
DNA barcoding DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that by comparison with a reference library of such DNA sections (also called "sequences"), an indiv ...
. This is not always possible, however, for archival specimens or samples such as microscopic slides from air samples.


Ecological importance

Aquatic or Ingoldian hyphomycetes are common on submerged decaying leaves and other organic matter, especially in clean running water with good aeration. Colonised leaves fall from the tree into the river. Their branched, septate mycelium penetrates through the leaf surface and spreads through leaf tissue. Conidiophores project into the water and bear conidia, which are often sigmoid, branched or tetraradiate structures. Aquatic hyphomycetes play an important role in the breakdown of organic matter in rivers, because their extracellular enzymes break down leaf tissue, which in turn is made more palatable to invertebrates. Leaves with fungi (conditioned) are a more nutritious source of food than unconditioned leaves. Coprophilous or dung-loving hyphomycetes are part of the succession of fungi occurring on many kinds of
herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...
faeces, playing an important role in breaking down
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...
. Several species are found only on dung, such as '' Angulimaya sundara'', '' Onychophora coprophila'', '' Pulchromyces fimicola'', '' Sphondylocephalum verticillatum'' and ''
Stilbella fimetaria ''Stilbella'' is a genus of fungi in the family Bionectriaceae (order Hypocreales). A 1985 monograph includes 19 species. More recent estimates place about 60 species in the genus. The type species ''Stilbella fimetaria'' (syn. ''Stilbella er ...
''. Entomogenous, entomopathogenic or insect-pathogenic hyphomycetes infect and kill insects (and spiders) and are especially diverse in tropical and subtropical regions, especially in Asia. Most are asexual states of or phylogenetically related to the Ascomycete families,
Cordycipitaceae The Cordycipitaceae are a family of parasitic fungi in the Ascomycota, class Sordariomycetes and order Hypocreales. The family was first published in 1969 by mycologist Hanns Kreisel, but the naming was invalid according to the code of Internati ...
and
Ophiocordycipitaceae Ophiocordycipitaceae is a family of parasitic fungi in the Ascomycota, class Sordariomycetes. Genera *'' Blistum'' *'' Didymobotryopsis'' *'' Haptocillium'' *'' Harposporium'' (Anamorphic) *'' Ophiocordyceps''; anamorphic genera: **''Hirsutella ...
. Insect hosts are infected by asexual spores, which germinate and grow to fill the host body with
mycelium Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrate (biology), substrates. A typical single ...
or hyphal bodies, then produce sporulating structures on the insect carcass. They are often found on dead insects under bark or in soil, but some affect insect behaviour (" zombie fungus"), causing infected hosts to climb towards the light, ensuring that air-borne infective spores will be released higher up in the
canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...
of the forest or meadow. Well-known entomogenous hyphomycetes are classified in ''
Beauveria ''Beauveria'' is a genus of asexually-reproducing fungi allied with the ascomycete family Cordycipitaceae. Its several species are typically insect pathogens. The sexual states (teleomorphs) of ''Beauveria'' species, where known, are species of ...
'', ''
Metarhizium ''Metarhizium'' is a genus of entomopathogenic fungi in the Clavicipitaceae family. With the advent of genetic profiling, placing these fungi in proper taxa has now become possible. Most turn out to be the asexual forms (anamorphs) of fungi in ...
'' and ''
Tolypocladium ''Tolypocladium'' is a genus of fungi within the family Ophiocordycipitaceae. It includes species that are parasites of other fungi, insect pathogens, rotifer pathogens and soil inhabiting species with uncertain ecological roles. ''Tolypocladium' ...
''; famous anamorphic
generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...
names such as ''
Akanthomyces ''Akanthomyces'' is a genus of fungi belonging to the family Cordycipitaceae and consisting of parasites of spiders and Lepidoptera. The genus was first described by Lebert in 1858. The genus has cosmopolitan distribution In biogeography, ...
'', ''
Gibellula ''Gibellula pulchra'' is a species of parasitic fungus found on arachnids. The species ''Gibellula pulchra'' is commonly found around the world. The genus ''Gibellula'' was named after Prof. Giuseppe Gibelli. Some researchers have mistaken '' ...
'', ''
Hirsutella ''Hirsutella'' is a genus of asexually reproducing fungi in the Ophiocordycipitaceae family. Originally described by French mycologist Narcisse Théophile Patouillard in 1892, this genus includes species that are pathogens of insects, mites and ne ...
'', ''
Hymenostilbe ''Hymenostilbe'' is a genus of fungi in the Ophiocordycipitaceae family. All members are anamorph names of ''Ophiocordyceps ''Ophiocordyceps'' is a genus of fungi within the family Ophiocordycipitaceae. The widespread genus, first described s ...
'' and ''
Isaria ''Isaria'' is a genus of fungi mostly in the order Hypocreales and family Clavicipitaceae, or by some authorities the Cordycipitaceae. It includes a large number of entomopathogenic species, some of them exploited as biopesticides (''e.g. I. ...
'' are now subsumed in genera formerly considered sexual, such as ''
Cordyceps ''Cordyceps'' is a genus of ascomycete fungi (sac fungi) that includes about 600 species. Most ''Cordyceps'' species are endoparasitoids, parasitic mainly on insects and other arthropods (they are thus entomopathogenic fungi); a few are parasiti ...
'', ''
Ophiocordyceps ''Ophiocordyceps'' is a genus of fungi within the family Ophiocordycipitaceae. The widespread genus, first described scientifically by British mycologist Tom Petch in 1931, contains about 140 species that grow on insects. Anamorphic genera that c ...
'' and '' Torubiella'' under fungal single-name nomenclature. Species of ''Beauveria'' and ''Metarhizium'' show some promise as
biological control agent Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
s against pest insects. ''
Tolypocladium inflatum ''Tolypocladium inflatum'' is an ascomycete fungus originally isolated from a Norwegian soil sample that, under certain conditions, produces the immunosuppressant drug ciclosporin. In its sexual stage (teleomorph) it is a parasite on scarab beetl ...
'' was the original source of
cyclosporine A Ciclosporin, also spelled cyclosporine and cyclosporin, is a calcineurin inhibitor, used as an immunosuppressant medication. It is a natural product. It is taken orally or intravenously for rheumatoid arthritis, psoriasis, Crohn's disease ...
, used as a drug to prevent rejection of
organ transplant Organ transplantation is a medical procedure in which an organ is removed from one body and placed in the body of a recipient, to replace a damaged or missing organ. The donor and recipient may be at the same location, or organs may be transpo ...
s. Many food-borne fungi are hyphomycetes. Species of ''Penicillium'' and ''Aspergillus'' are particularly common agents of food spoilage and also produce important mycotoxins that affect human health. Some species, such as ''Penicillium digitatum'' on citrus fruits, and ''Penicillium expansum'' on apples, are common on specific foods, while others are less specialized and grow on many different kinds of food. Nematophagous or nematode-trapping hyphomycetes either live their life-cycles in the bodies of dead nematodes or trap and kill nematodes in order to supplement their
nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
requirements. Species of the hyphomycete genus ''
Arthrobotrys ''Arthrobotrys'' is a genus of mitosporic fungi in the family Orbiliaceae. There are 71 species. They are predatory fungi that capture and feed on nematode worms. Rings that form on the hyphae constrict and entrap the worms, then hyphae grow int ...
'', phylogenetically related to or being the asexual forms of '' Orbilia'', produce constricting loops that quickly shut to grab nematodes, or non-constricting loops or hyphal networks that entangle nematodes, or sticky knobs that adhere to nematodes as they swim by. Attempts to exploit these fungi as biological control agents against agriculturally harmful nematodes have generally been unsuccessful.


See also

*''
Acremonium ''Acremonium'' is a genus of fungi in the family Hypocreaceae. It used to be known as ''Cephalosporium''. Description ''Acremonium'' species are usually slow-growing and are initially compact and moist. Their hyphae are fine and hyaline, and pro ...
'' *''
Alternaria ''Alternaria'' is a genus of Deuteromycetes fungi. All species are known as major plant pathogens. They are also common allergens in humans, growing indoors and causing hay fever or hypersensitivity reactions that sometimes lead to asthma. They ...
'' *''
Aspergillus ' () is a genus consisting of several hundred mold species found in various climates worldwide. ''Aspergillus'' was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Miche ...
'' *''
Beauveria ''Beauveria'' is a genus of asexually-reproducing fungi allied with the ascomycete family Cordycipitaceae. Its several species are typically insect pathogens. The sexual states (teleomorphs) of ''Beauveria'' species, where known, are species of ...
'' *''
Chrysosporium ''Chrysosporium'' is a genus of hyaline hyphomycetes fungi in the family Onygenaceae. ''Chrysosporium'' colonies are moderately fast-growing, flat, white to tan to beige in color; they often have a powdery or granular surface texture. Hyaline, ...
'' *''
Cladosporium ''Cladosporium'' is a genus of fungi including some of the most common indoor and outdoor molds. Species produce olive-green to brown or black colonies, and have dark-pigmented conidia that are formed in simple or branching chains. Many species ...
'' *''
Fusarium ''Fusarium'' is a large genus of filamentous fungi, part of a group often referred to as hyphomycetes, widely distributed in soil and associated with plants. Most species are harmless saprobes, and are relatively abundant members of the soil mi ...
'' *''
Geomyces ''Geomyces'' is a genus of filamentous fungi in the family Myxotrichaceae. Members of the genus are widespread in distribution, especially in northern temperate regions. Known to be psychrotolerant and associated with Arctic permafrost soils, ...
'' *''
Geotrichum Geotrichum is a genus of fungi found worldwide in soil, water, air, and sewage, as well as in plants, cereals, and dairy products; it is also commonly found in normal human flora and is isolated from sputum and feces. It was first described in ...
'' *''
Gliocladium ''Gliocladium''Corda (1840) ''Icon. fung. (Prague)'' 4: 30. is an asexual fungal genus in the Hypocreaceae. Certain other species including ''Gliocladium virens'' were recently transferred to the genus ''Trichoderma'' and ''G. roseum'' became '' ...
'' *'' Graphium'' *''
Isaria ''Isaria'' is a genus of fungi mostly in the order Hypocreales and family Clavicipitaceae, or by some authorities the Cordycipitaceae. It includes a large number of entomopathogenic species, some of them exploited as biopesticides (''e.g. I. ...
'' *''
Madurella ''Madurella'' is a fungal genus of Hyphomycetes, of uncertain position in the Sordariales, and sometimes classified as Mitosporic Ascomycota. It includes: * '' Madurella grisea'' * ''Madurella mycetomatis'' ''Madurella mycetomatis'' is a main ...
'' *'' Malbranchea'' *''
Paecilomyces ''Paecilomyces'' is a genus of fungi. A number of species in this genus are plant pathogens. Several of the entomopathogenic species, such as "'' Paecilomyces fumosoroseus''" have now been placed in the genus ''Isaria'': in the order Hypocreale ...
'' *''
Penicillium ''Penicillium'' () is a genus of ascomycetous fungi that is part of the mycobiome of many species and is of major importance in the natural environment, in food spoilage, and in food and drug production. Some members of the genus produce pe ...
'' *''
Scedosporium ''Scedosporium'' is a genus of fungi in the family Microascaceae. The genus shed the alternative name '' Pseudallescheria'' as the " One Fungus, One Name" principle overtook the previous dual naming system, which had a distinct names for the an ...
'' *''
Scopulariopsis ''Scopulariopsis'' is a genus of teleomorph, anamorph and holomorph, anamorphic fungi that are saprobic and pathogenic to animals. The widespread genus contains 22 species. ''Scopulariopsis'' belongs to the group Hyphomycetes. These species are c ...
'' *'' Sepedonium'' *''
Stachybotrys ''Stachybotrys'' () is a genus of molds, hyphomycetes or asexually reproducing, filamentous fungi, now placed in the family Stachybotryaceae. The genus was erected by August Carl Joseph Corda in 1837. Historically, it was considered closely re ...
'' *''
Tolypocladium ''Tolypocladium'' is a genus of fungi within the family Ophiocordycipitaceae. It includes species that are parasites of other fungi, insect pathogens, rotifer pathogens and soil inhabiting species with uncertain ecological roles. ''Tolypocladium' ...
'' *''
Trichoderma ''Trichoderma'' is a genus of fungi in the family Hypocreaceae that is present in all soils, where they are the most prevalent culturable fungi. Many species in this genus can be characterized as opportunistic avirulent plant symbionts. This ref ...
'' *'' Trichothecium'' *''
Verticillium ''Verticillium'' is a genus of fungi in the division Ascomycota, and are an anamorphic form of the family Plectosphaerellaceae. The genus used to include diverse groups comprising saprobes and parasites of higher plants, insects, nematodes, mo ...
'' *'' Wallemia''


References


Literature

*


External links

*http://www.generaofhyphomycetes.org *https://web.archive.org/web/20070501103624/http://www.mycology.adelaide.edu.au/Fungal_Descriptions/Hyphomycetes_(hyaline)/ *https://web.archive.org/web/20070602115822/http://www-biol.paisley.ac.uk/bioref/Fungi/Botrytis_cinerea.html {{Taxonbar, from=Q1046151 Deuteromycota Obsolete fungus taxa Ascomycota