Fungi imperfecti

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Fungi imperfecti
Aspergillus.gif
Conidiophore of Aspergillus sp.
Scientific classification
Kingdom:
Species

See below.

The fungi imperfecti or imperfect fungi are fungi which do not fit into the commonly established taxonomic classifications of fungi that are based on biological species concepts or morphological characteristics of sexual structures because their sexual form of reproduction has never been observed. They are known as imperfect fungi because only their asexual and vegetative phases are known. They have asexual form of reproduction, meaning that these fungi produce their spores asexually, in the process called sporogenesis.

Contents

There are about 25,000 species that have been classified in the deuteromycota and many are basidiomycota or ascomycota anamorphs. Fungi producing the antibiotic penicillin and those that cause athlete's foot and yeast infections are algal fungi. In addition, there are a number of edible imperfect fungi, including the ones that provide the distinctive characteristics of Roquefort and Camembert cheese.

Other, more informal names besides Deuteromycota ("Deuteromycetes") and fungi imperfecti are anamorphic fungi, or mitosporic fungi, but these are terms without taxonomic rank. Examples are Alternaria, Colletotrichum, Trichoderma etc.

Problems in taxonomic classification

Although Fungi imperfecti/Deuteromycota is no longer formally accepted as a taxon, many of the fungi it included have yet to find a place in modern fungal classification. This is because most fungi are classified based on characteristics of the fruiting bodies and spores produced during sexual reproduction, and members of the Deuteromycota have been observed to reproduce only asexually or produce no spores.

Mycologists are unique among those who study extant organisms in using a dual system of nomenclature. Dual naming was permitted by Article 59 of the International Code of Botanical Nomenclature (which governs the naming of plants and fungi); however, this was abolished in the 2011 update of the Code. [1]

Under the former system, a name for an asexually reproducing fungus was considered a form taxon. For example, the ubiquitous and industrially important mold, Aspergillus niger , has no known sexual cycle. Thus Aspergillus niger is considered a form taxon. In contrast, isolates of its close relative, Aspergillus nidulans , revealed it to be the anamorphic stage of a teleomorph (the ascocarp or fruiting body of the sexual reproductive stage of a fungus), which was already named Emericella nidulans. When such a teleomorphic stage is known, that name will take priority over the name of an anamorph (which lacks a sexual reproductive stage). Hence the formerly classified Aspergillus species is now properly called Emericella nidulans.

Phylogeny and taxonomy

Phylogenetic classification of asexually reproducing fungi now commonly uses molecular systematics. Phylogenetic trees constructed from comparative analyses of DNA sequences, such as rRNA, or multigene phylogenies may be used to infer relationships between asexually reproducing fungi and their sexually reproducing counterparts. With these methods, many asexually reproducing fungi have now been placed in the tree of life.[ citation needed ] However, because phylogenetic methods require sufficient quantities of biological materials (spores or fresh specimens) that are from pure (i.e., uncontaminated) fungal cultures, for many asexual species their exact relationship with other fungal species has yet to be determined. Under the current system of fungal nomenclature, teleomorph names cannot be applied to fungi that lack sexual structures. Classifying and naming asexually reproducing fungi is the subject of ongoing debate in the mycological community.

Historical classification of the imperfect fungi

These groups are no longer formally accepted because they do not adhere to the principle of monophyly.[ citation needed ] The taxon names are sometimes used informally. In particular, the term 'hyphomycetes' is often used to refer to molds, and the term 'coelomycetes' is used to refer to many asexually reproducing plant pathogens that form discrete fruiting bodies.

Following, a classification of the Fungi imperfecti: Saccardo et al.(1882-1972) [2]

Other, according to Dörfelt (1989): [3]

Other systems of classification are reviewed by ( Kendrick 1981 ).

Common species

Industrially relevant fungi

See also

Related Research Articles

<span class="mw-page-title-main">Ascomycota</span> Division or phylum of fungi

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 defining feature of this fungal group is the "ascus", a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of Ascomycota are asexual and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens such as Cladonia belong to the Ascomycota.

<span class="mw-page-title-main">Mold</span> Wooly, dust-like fungal structure or substance

A mold or mould is one of the structures that certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites. The spores are the dispersal units of the fungi. Not all fungi form molds. Some fungi form mushrooms; others grow as single cells and are called microfungi.

<i>Penicillium</i> Genus of fungi

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.

In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota:

<i>Aspergillus</i> Genus of fungi

Aspergillus is a genus consisting of several hundred mold species found in various climates worldwide.

<i>Sarcoscypha</i> Genus of fungi

Sarcoscypha is a genus of ascomycete fungus and a type genus of the family Sarcoscyphaceae. Species of Sarcoscypha are present in Europe, North America and tropical Asia. They are characterised by a cup-shaped apothecium which is often brightly coloured. They have had a range of popular uses, one of which was as a table decoration. Some members of the family such as S. coccinea and the - according to new knowledge - more common S. austriaca in western Europe and United States have bright scarlet apothecia which have given them familiar names such as the scarlet cup fungus and scarlet elf cap.

An entomopathogenic fungus is a fungus that can kill or seriously disable insects. They do not need to enter an insect's body through oral ingestion or intake; rather, they directly penetrate though the exoskeleton.

Metarhizium robertsii is a fungus that grows naturally in soils throughout the world and causes disease in various insects by acting as a parasitoid. It is a mitosporic fungus with asexual reproduction, which was formerly classified in the form class Hyphomycetes of the phylum Deuteromycota.

<span class="mw-page-title-main">Saccharomycotina</span> Subdivision of fungi

Saccharomycotina is a subdivision (subphylum) of the division (phylum) Ascomycota in the kingdom Fungi. It comprises most of the ascomycete yeasts. The members of Saccharomycotina reproduce by budding and they do not produce ascocarps.

<span class="mw-page-title-main">Leotiomycetes</span> Class of fungi

The Leotiomycetes are a class of ascomycete fungi. Many of them cause serious plant diseases.

This is a glossary of some of the terms used in phytopathology.

Hyphomycetes are a form classification of fungi, part of what has often been referred to as fungi imperfecti, Deuteromycota, or anamorphic fungi. Hyphomycetes lack closed fruit bodies, and are often referred to as moulds. Most hyphomycetes are now assigned to the Ascomycota, on the basis of genetic connections made by life-cycle studies or by phylogenetic analysis of DNA sequences; many remain unassigned phylogenetically.

<span class="mw-page-title-main">Pycnidium</span> Fungal spore-bearing structure

A pycnidium is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales or order Pleosporales. It is often spherical or inversely pearshaped (obpyriform) and its internal cavity is lined with conidiophores. When ripe, an opening generally appears at the top, through which the pycnidiospores escape.

<span class="mw-page-title-main">Fungus</span> Biological kingdom, separate from plants and animals

A fungus 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 one of the traditional eukaryotic kingdoms, along with Animalia, Plantae and either Protista or Protozoa and Chromista.

<i>Dendrocollybia</i> Genus of fungi in the family Tricholomataceae

Dendrocollybia is a fungal genus in the family Tricholomataceae of the order Agaricales. It is a monotypic genus, containing the single species Dendrocollybia racemosa, commonly known as the branched collybia or the branched shanklet. The somewhat rare species is found in the Northern Hemisphere, including the Pacific Northwest region of western North America, and Europe, where it is included in several Regional Red Lists. It usually grows on the decaying fruit bodies of other agarics—such as Lactarius and Russula—although the host mushrooms may be decayed to the point of being difficult to recognize.

<i>Sarcoscypha occidentalis</i> Species of fungus

Sarcoscypha occidentalis, commonly known as the stalked scarlet cup or the western scarlet cup, is a species of fungus in the family Sarcoscyphaceae of the Pezizales order. Phylogenetic analysis has shown that it is most closely related to other Sarcoscypha species that contain large oil droplets in their spores. S. occidentalis has an imperfect form, classified as Molliardiomyces occidentalis.

Coelomycetes are a form-class of fungi, part of what has often been referred to as fungi imperfecti, Deuteromycota, or anamorphic fungi.

<i>Myxotrichum chartarum</i> Species of fungus

Myxotrichum chartarum is a psychrophilic and cellulolytic fungus first discovered in Germany by Gustav Kunze in 1823. Its classification has changed many times over its history to better reflect the information available at the time. Currently, M. chartarum is known to be an ascomycete surrounded by a gymnothecium composed of ornate spines and releases asexual ascospores. The presence of cellulolytic processes are common in fungi within the family Myxotrichaceae. M. chartarum is one of many Myxotrichum species known to degrade paper and paper products. Evidence of M. chartarum "red spot" mold formation, especially on old books, can be found globally. As a result, this fungal species and other cellulolytic molds are endangering old works of art and books. Currently, there is no evidence that suggests that species within the family Myxotrichaceae are pathogenic.

<span class="mw-page-title-main">Glossary of mycology</span>

This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found in glossary of biology and glossary of botany, among others. List of Latin and Greek words commonly used in systematic names and Botanical Latin may also be relevant, although some prefixes and suffixes very common in mycology are repeated here for clarity.

Savoryellaceae is a family of aquatic based fungi. It is the only family in the monotypic order Savoryellales within the class Sordariomycetes, division Ascomycota.

References

  1. "International Code of Nomenclature for algae, fungi, and plants". International Association for Plant Taxonomy.
  2. "Fungi - Wikispecies".
  3. Dörfelt, Heinrich (Hrsg.): Lexikon der Mykologie. Gustav Fischer Verlag, Stuttgart, New York. 1989.
  4. See "Una Historia Ilustrada del Transplante de Órganos" Archived 2008-03-16 at the Wayback Machine (in Spanish).
  5. See the following link Archived 2008-09-09 at the Wayback Machine (in Spanish).
  6. "Bio-Cat Products". Bio-Cat. Archived from the original on 2008-12-04. Retrieved 2008-10-02.{{cite web}}: More than one of |archivedate= and |archive-date= specified (help); More than one of |archiveurl= and |archive-url= specified (help)
  7. "ARS en Espanol : News & Events". USDA. Archived from the original on 2008-10-12. Retrieved 2008-10-02.
  8. "Enzyme Development Corporation". Archived from the original on 2012-03-21. Retrieved 2008-10-02.
  9. See this link Archived 2011-07-07 at the Wayback Machine (in Spanish).
  10. Cf. Archived 2008-10-06 at the Wayback Machine (in Spanish).

Bibliography