- Source: Zoopagomycotina
The Zoopagomycotina are a subdivision (incertae sedis) of the fungal division Zygomycota sensu lato. It contains 5 families and 20 genera. Relationships among and within subphyla of Zygomycota are poorly understood, and their monophyly remains in question, so they are sometimes referred to by the informal name zygomycetes.
Zoopagomycotina are microscopic and are typically obligate parasites of other zygomycete fungi and of microscopic soil animals such as nematodes, rotifers and amoebae. Some species are endoparasites that live mostly within the bodies of their hosts and only exit the host when they are producing spores. Other species are ectoparasites (e.g. Syncephalis, Piptocephalis) that live outside of the host body but produce specialized organs called haustoria that penetrate inside of the host body to capture host nutrients. Similar haustoria are found in biotrophic plant, animal and fungal pathogens in several other major fungal lineages.
Like most other zygomycete fungi, the Zoopagomycotina have cell walls containing chitin and have coenocytic (nonseptate) hyphae. Their vegetative body consists of a simple, branched or unbranched thallus. Asexual reproduction is by arthrospores (in Helicocephalum), chlamydospores, uni- or multi-spored sporganiola; sporangiospores of multi-spored formed in simple or branched chains (merosporangia), usually from a vesicle or stalk. Many produce haustoria. Where observed, the sexual spores (zygospores) are globose and unornamented. The hyphae used during sexual outcrossing is similar to vegetative hyphae or in some cases may be slightly enlarged.
Etymology
The word Zoopagomycotina comes from the Greek roots zoo meaning "animal" and pag meaning "rock" or "ice/frost".
Evolutionary relationships
Although great strides have been made in resolving the evolutionary relationships among many lineages of fungi, it has been challenging to resolve relationships within and among zygomycetes. For example, the uncertain grouping of Zoophagus insidians with the Kickxellomycotina.
Resolving a well-supported monophyly of the Zoopagomycotina has been particularly challenging for several main reasons:
most species of Zoopagomycotina are microscopic and challenging to observe
most species of Zoopagomycotina cannot be grown separately from their host organisms in axenic culture, so obtaining pure DNA for molecular studies is challenging
based on ribosomal DNA sequences, species of Zoopagomycotina may have undergone accelerated evolution, so grouping may be skewed by long-branch attraction (LBA) and a high frequency of parallel evolutionary changes
Families and their respective genera
Class Zoopagomycetes Doweld 2014
Order Zoopagales Bessey 1950 ex. Benjamin 1979 [Zoophagales Doweld 2014]
Massartia De Wildeman 1897 non Conrad 1926
Family Basidiolaceae Doweld 2013
Basidiolum Cienk. 1861
Family Cochlonemataceae Duddington 1974
Amoebophilus (6 spp.) ectoparasite of amoebae
Aenigmatomyces Castan˜eda & Kendrick 1993
Aplectosoma (1 sp.) parasite of an amoeba
Bdellospora (1 sp.) ectoparasite of an amoeba
Cochlonema (19 spp.) endoparasites of amoebae and rhizopods
Endocochlus (4 spp.) endoparasites of amoebae
Euryancale (5 spp. ) endoparasites of nematodes
Family Helicocephalidaceae Boedijn 1959
Brachymyces (1 sp.) parasitic on bdelloid rotifers
Helicocephalum (5 spp.) parasites of small animals, especially nematodes and nematode eggs
Rhopalomyces (8 spp.) parasites of small animals, especially nematodes and nematode eggs
Verrucocephalum Degawa 2013
Family Piptocephalidaceae Schröter 1886
Kuzuhaea (1 sp.) haustorial parasite of fungi (mostly of Mucorales spp.)
Piptocephalis (25 spp.) haustorial parasite of fungi (mostly of Mucorales spp.)
Syncephalis (61 spp.) haustorial parasite of fungi (mostly of Mortierellales and Mucorales spp.)
Family Sigmoideomycetaceae Benny, Benjamin & Kirk 1992
Reticulocephalis (2 spp.) putative haustorial parasite of fungi
Sigmoideomyces (2 spp.) putative haustorial parasite of fungi
Sphondylocephalum Stalpers 1974
Thamnocephalis (3 spp.) haustorial parasite of fungi
Family Zoopagaceae Drechsler 1938
Acaulopage (27 spp.) haustorial parasites of amoeba
Cystopage (7 spp.) haustorial parasites of amoebae and nematodes
Lecophagus Dick 1990
Stylopage (18 spp.) predaceous on amoebae and nematodes
Tentaculophagus Doweld 2014
Zoopage (11 spp.) haustorial parasite of amoebae and testaceous rhizopods
Zoophagus (5 spp.) ectoparasites of loricate rotifers and nematodes
References
External links
Zygomycota at the Tree of Life Web Project
Zygomycetes.org
Zoopagomycotina in MycoBank.
https://www.uniprot.org/taxonomy/451827
https://web.archive.org/web/20110720003551/http://agclass.canr.msu.edu/mtwdk.exe?w=125844&k=default&s=5&t=2&n=1&l=60