Hyphochytrids are

eukaryotic The eukaryotes ( ) constitute the Domain (biology), domain of Eukaryota or Eukarya, organisms whose Cell (biology), cells have a membrane-bound cell nucleus, nucleus. All animals, plants, Fungus, fungi, seaweeds, and many unicellular organisms ...

organisms in the group of

Stramenopiles The stramenopiles, also called heterokonts, are Protist, protists distinguished by the presence of stiff tripartite external hairs. In most species, the hairs are attached to flagella, in some they are attached to other areas of the cellular sur ...

(Heterokonta).

Characteristics

They are distinguished by an anterior tinsel flagellum on their

zoospores A zoospore is a motile asexual spore that uses a flagellum for locomotion in aqueous or moist environments. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Certain zoospores are ...

. Also they have a rhizoidal or hypha-like vegetative system (hence the prefix "Hypho-").

Classification

This group may be put alternatively at the phylum, class, subclass or order level, being referred to as Hyphochytriomycota, Hyphochytriomycetes (or Hyphochytrea), Hyphochytriomycetidae (or Hyphochytridae) and Hyphochytriales, respectively. The variants Hyphochytri''di''omycota and Hyphochytri''di''omycetes are also sometimes used, presumably by analogy to the Chytridiomycetes, or due to the perpetuation of a typographical error. However, the stem is Hyphochytri- (from '' Hyphochytrium'') and not Hyphochytridi- (from ''

Chytridium ''Chytridium'' is a genus of fungi in the family Chytridiaceae. With the culture and characterization of Chytridium olla, the type species of the order, the limits of the Chytridiales were established. ; Names brought to synonymy: * ''Chytridi ...

''). In the past the classes Hyphochytridiomycetes,

Oomycetes The Oomycetes (), or Oomycota, form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms within the Stramenopiles. They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction o ...

and

Chytridiomycetes Chytridiomycetes () is a class of fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushr ...

were grouped together in the now obsolete taxon

Mastigomycotina Mastigomycotina is a former polyphyletic taxonomic grouping, a subdivision, of fungi, similar to Phycomycetes, and that included the zoosporic classes Chytridiomycetes, Hyphochytriomycetes, Plasmodiophoromycetes and Oomycetes. General feat ...

as fungi with flagellate spores or gametes. Now the Chytridiomycetes are still considered true fungi, but the other two sub-groups are classified in the kingdom

Protista A protist ( ) or protoctist is any Eukaryote, eukaryotic organism that is not an animal, Embryophyte, land plant, or fungus. Protists do not form a Clade, natural group, or clade, but are a Paraphyly, paraphyletic grouping of all descendants o ...

, or in the group

. Hyphochytriomycetes are closely related to

. Order Hyphochytriales Bessey 1950 ex Sparrow 1960 * Family Hyphochytriaceae Fischer 1892 ** Genus '' Canteriomyces'' Sparrow 1960 ** Genus '' Cystochytrium'' Ivimey Cook 1932 ** Genus '' Hyphochytrium'' Zopf 1884 'Hyphophagus'' Minden 1911">Hyphophagus.html" ;"title="'Hyphophagus">'Hyphophagus'' Minden 1911* Family Rhizidiomycetaceae Karling ex Kirk, Cannon & David 2001 ** Genus ''Latrostium'' Zopf 1894 ** Genus ''Reessia'' Fisch 1883 ** Genus ''Rhizidiomyces'' Zopf 1884 'Rhizidiomycopsis'' Sparrow 1960">Rhizidiomycopsis.html" ;"title="'Rhizidiomycopsis">'Rhizidiomycopsis'' Sparrow 1960

Diversity

This is a relatively small group, composed of about 16 known species, which may be due in part, to sampling methods of scientists.

References

Bibliography

*C.J. Alexopolous, Charles W. Mims, M. Blackwell et al., ''Introductory Mycology'', 4th ed. John Wiley and Sons, Hoboken NJ, 2004. . *

External links