Zygomycota |
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Sporangium of a Phycomyces sp. |
Scientific classification |
Kingdom: |
Fungi |
Phylum: |
Zygomycota
C. Moreau 1954 (informal) |
Class: |
Zygomycetes
Winter 1881 |
Orders |
Mucoromycotina:
- Endogonales
- Mucorales
- Mortierellales
Kickxellomycotina:
- Asellariales
- Kickxellales
- Dimargaritales
- Harpellales
Entomophthoromycotina:
Zoopagomycotina:
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Zygomycota, or zygote fungi, is a phylum of fungi. The name comes from zygosporangia, where resistant spherical spores are formed during sexual reproduction. Approximately 1060 species are known. They are mostly terrestrial in habitat, living in soil or on decaying plant or animal material. Some are parasites of plants, insects, and small animals, while others form symbiotic relationships with plants.[1] Zygomycete hyphae may be coenocytic, forming septa only where gametes are formed or to wall off dead hyphae.
Contents
- 1 Reproduction
- 2 Phylogeny
- 3 Evolution of conidia
- 4 References
- 5 External links
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Reproduction
An example of a zygomycete is black bread mold (Rhizopus stolonifer), a member of the Mucorales. It spreads over the surface of bread and other food sources, sending hyphae inward to absorb nutrients. In its asexual phase it develops bulbous black sporangia at the tips of upright hyphae, each containing hundreds of haploid spores.
As in most zygomycetes, asexual reproduction is the most common form of reproduction. Sexual reproduction in Rhizopus stolonifer, as in other zygomycetes, occurs when haploid hyphae of different mating types are in close proximity to each other. Growth of the gametangia commences after gametangia come in contact, and plasmogamy, or the fusion of the cytoplasm, occurs. Karyogamy, which is the fusion of the nuclei, follows closely after. The zygosporangia are then diploid. Zygosporangia are typically thick-walled, highly resilient to environmental hardships, and metabolically inert. When conditions improve, however, they germinate to produce a sporangium or vegetative hyphae. Meiosis occurs during germination of the zygosporagium so the resulting spores or hyphae are haploid. Grows in warm and damp conditions.
Some zygomycetes disperse their spores in a more precise manner than simply allowing them to drift aimlessly on air currents. Pilobolus, a fungus which grows on animal dung, bends its sporangiophores towards light with the help of a light sensitive pigment (beta-carotene) and then "fires" them with an explosive squirt of high-pressure cytoplasm. Sporangia can be launched as far as 2 m, placing them far away from the dung and hopefully on vegetation which will be eaten by an herbivore, eventually to be deposited with dung elsewhere. Different mechanisms for forcible spore discharge have evolved among members of the zygomycete order Entomophthorales.
Phylogeny
The Zygomycota are generally placed near the base of the fungal phylogenetic tree, having diverged from other fungi after chytrids.
Molecular phylogenetics reveals that they form a polyphyletic group and could see a split into several new phyla.[2]
The order Glomales was removed in 2001 and elevated to Division (or phylum) Glomeromycota[3][4] due to their lack of zygospore formation, mycorrhizal habit, and lack of DNA sequence homology.
Evolution of conidia
The evolution of the conidium from the sporangiospore is the main defining difference between Zygomycetes and Ascomycetes.[5] The evolution of sporangiospores typical of zygomycetes to conidia similar to those found in ascomycetes can be modeled by a series of forms seen in zygomycetes. Many zygomycetes produce multiple sporangiospores inside a single sporangium. Some have evolved multiple small sporangiola that contain few sporangiospores. In some cases, there may be a few as three spores in each sporangiolum, and a few species have sporangiola which contain just a single spore. "Choanephora", a zygomycete, has a sporangiolum that contains one spore with a sporangium wall that is visible at the base of the sporangium. This structure is similar to a conidium, which has two, fused cell walls, an inner spore wall and an outer sporangium wall.
References
- ^ . Raven, P. H., Evert, R. F., & Eichhorn, S. E. (2005). Fungi. In Biology of plants (pp/ 268-269). New York: W.H. Freeman and Company.
- ^ Hibbett DS, Binder M, Bischoff JF, et al. (May 2007). "A higher-level phylogenetic classification of the Fungi". Mycol. Res. 111 (Pt 5): 509–47. doi:10.1016/j.mycres.2007.03.004. PMID 17572334. http://linkinghub.elsevier.com/retrieve/pii/S0953-7562(07)00061-5.
- ^ "Zygomycota". http://www.tolweb.org/Zygomycota. Retrieved 2009-03-07.
- ^ Schüßler A., Schwarzott D., Walker C. (2001). "A new fungal phylum, the Glycomycota: phylogeny and evolution". Mycol. Res. 105 (12): 1413–1421. doi:10.1017/S0953756201005196.
- ^ Cain, R. F. (1972). "Evolution of the Fungi". Mycologia 64 (1): 1–14. doi:10.2307/3758010. JSTOR 3758010.
External links
- Zygomycota at the Tree of Life Web Project
- Zygomycetes.org
- List of all Zygomycetes species from Zygomycetes database by PM Kirk in Catalogue of Life 2008
- Mucorales at the US National Library of Medicine Medical Subject Headings (MeSH)
Eukaryota
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- Domain : Archaea
- Bacteria
- Eukaryota
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Bikonta |
AH/SAR
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AH
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Archaeplastida, or Plantae sensu lato
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- Viridiplantae/Plantae sensu stricto
- Rhodophyta
- Glaucophyta
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Hacrobia, or non-SAR chromalveolata
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- Haptophyta
- Cryptophyta
- Centroheliozoa
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SAR
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Halvaria
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Heterokont ("S")
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- Ochrophyta
- Bigyra
- Pseudofungi
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Alveolata
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- Ciliates
- Myzozoa
- Apicomplexa
- Dinoflagellata
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Rhizaria
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Excavata
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- Discoba
- Euglenozoa
- Jakobea
- Percolozoa
- Loukozoa
- Metamonad
- Malawimonas
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Apusozoa
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- Apusomonadida
- Ancyromonadida
- Hemimastigida
- Hemimastix
- Spironema
- Stereonema
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Unikonta |
Amoebozoa
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- Lobosea
- Conosa
- Phalansterium
- Breviata
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Opisthokonta
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Holozoa
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Mesomycetozoea
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- Dermocystida
- Ichthyophonida
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Filozoa
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Filasterea
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Choanoflagellate
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- Codonosigidae
- Salpingoecidae
- Acanthoecidae
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Metazoa
or "Animalia"
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- Eumetazoa
- Bilateria
- Cnidaria
- Ctenophora
- Mesozoa
- Parazoa
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Holomycota
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Fungi
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- Dikarya
- Glomeromycota
- Zygomycota
- Blastocladiomycota
- Chytridiomycota
- Neocallimastigomycota
- Microsporidia
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Nucleariidae
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- Nuclearia
- Micronuclearia
- Rabdiophrys
- Pinaciophora
- Pompholyxophrys
- Fonticula
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Unclassified |
Diphyllatea
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- Collodictyon triciliatum
- Diphylleia rotans
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Opisthokont: Fungi classification, fungal orders
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Dikarya |
Ascomycota |
saccharomyceta |
Pezizomycotina |
leotiomyceta |
- Geoglossomycetes
- dothideomyceta (Arthoniomycetes/ Dothideomycetes)
- Eurotiomycetes
- Lecanoromycetes
- sordariomyceta ((Leotiomycetes (Sordariomycetes/ Laboulbeniomycetes))
- Lichinomycetes
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Other |
- Orbiliomycetes
- Pezizomycetes
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Saccharomycotina |
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Taphrinomycotina |
- Archaeorhizomycetes
- Neolectomycetes
- Pneumocystidomycetes
- Schizosaccharomycetes
- Taphrinomycetes
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Basidiomycota |
- Pucciniomycotina
- Ustilaginomycotina
- Agaricomycotina
- Urediniomycetes
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Glomeromycota |
- Glomerales
- Diversisporales
- Paraglomerales
- Archaeosporales
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Zygomycota |
Mucoromycotina |
- Endogonales
- Mucorales
- Chaetocladiaceae
- Choanephoraceae
- Cunninghamellaceae
- Gilbertellaceae
- Mortierellaceae
- Mucoraceae
- Mycotyphaceae
- Phycomycetaceae
- Pilobolaceae
- Radiomycetaceae
- Saksenaeaceae
- Syncephalastraceae
- Thamnidiaceae
- Umbelopsidaceae
- Mortierellales
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Entomophthoromycotina |
- Entomophthorales
- Basidiobolaceae
- Ancylistaceae
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Kickxellomycotina |
- Asellariales
- Kickxellales
- Dimargaritales
- Harpellales
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Zoopagomycotina |
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Other |
- Blastocladiomycota
- Chytridiomycota/Neocallimastigomycota
- Microsporidia
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Infectious diseases · Mycoses and Mesomycetozoea (B35–B49, 110–118)
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Superficial and
cutaneous
(dermatomycosis):
Tinea=skin;
Piedra (exothrix/
endothrix)=hair |
Ascomycota
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Dermatophyte
(Dermatophytosis)
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By location
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Tinea barbae/Tinea capitis (Kerion) · Tinea corporis (Ringworm, Dermatophytid) · Tinea cruris · Tinea manuum · Tinea pedis (Athlete's foot) · Tinea unguium/Onychomycosis (White superficial onychomycosis · Distal subungual onychomycosis · Proximal subungual onychomycosis)
Tinea corporis gladiatorum · Tinea faciei · Tinea imbricata · Tinea incognito · Favus
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By organism
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Epidermophyton floccosum · Microsporum canis · Microsporum audouinii · Trichophyton interdigitale/mentagrophytes · Trichophyton tonsurans · Trichophyton schoenleini · Trichophyton rubrum
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Other
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Hortaea werneckii (Tinea nigra) · Piedraia hortae (Black piedra)
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Basidiomycota
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Malassezia furfur (Tinea versicolor, Pityrosporum folliculitis) · Trichosporon spp (White piedra)
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Subcutaneous,
systemic,
and opportunistic |
Ascomycota
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Dimorphic
(yeast+mold)
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Onygenales
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Coccidioides immitis/Coccidioides posadasii (Coccidioidomycosis, Disseminated coccidioidomycosis, Primary cutaneous coccidioidomycosis. Primary pulmonary coccidioidomycosis) · Histoplasma capsulatum (Histoplasmosis, Primary cutaneous histoplasmosis, Primary pulmonary histoplasmosis, Progressive disseminated histoplasmosis) · Histoplasma duboisii (African histoplasmosis) · Lacazia loboi (Lobomycosis) · Paracoccidioides brasiliensis (Paracoccidioidomycosis)
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Other
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Blastomyces dermatitidis (Blastomycosis, North American blastomycosis, South American blastomycosis) · Sporothrix schenckii (Sporotrichosis) · Penicillium marneffei (Penicilliosis)
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Yeast-like
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Candida albicans (Candidiasis, Oral, Esophageal, Vulvovaginal, Chronic mucocutaneous, Antibiotic candidiasis, Candidal intertrigo, Candidal onychomycosis, Candidal paronychia, Candidid, Diaper candidiasis, Congenital cutaneous candidiasis, Perianal candidiasis, Systemic candidiasis, Erosio interdigitalis blastomycetica) · C. glabrata · C. tropicalis · C. lusitaniae · Pneumocystis jirovecii (Pneumocystosis, Pneumocystis pneumonia)
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Mold-like
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Aspergillus (Aspergillosis, Aspergilloma, Allergic bronchopulmonary aspergillosis, Primary cutaneous aspergillosis) · Exophiala jeanselmei (Eumycetoma) · Fonsecaea pedrosoi/Fonsecaea compacta/Phialophora verrucosa (Chromoblastomycosis) · Geotrichum candidum (Geotrichosis) · Pseudallescheria boydii (Allescheriasis)
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Basidiomycota
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Cryptococcus neoformans (Cryptococcosis), Trichosporon spp (Trichosporonosis)
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Zygomycota
(Zygomycosis)
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Mucorales
(Mucormycosis)
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Rhizopus oryzae · Mucor indicus · Absidia corymbifera · Syncephalastrum racemosum
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Entomophthorales
(Entomophthoramycosis)
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Basidiobolus ranarum (Basidiobolomycosis) · Conidiobolus coronatus/Conidiobolus incongruus (Conidiobolomycosis)
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Microsporidia
(Microsporidiosis)
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Enterocytozoon bieneusi/Encephalitozoon intestinalis
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Mesomycetozoea |
Rhinosporidium seeberi (Rhinosporidiosis)
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Ungrouped |
Alternariosis · Fungal folliculitis · Fusarium (Fusariosis) · Granuloma gluteale infantum · Hyalohyphomycosis · Otomycosis · Phaeohyphomycosis
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