Gyrista is a phylum of

heterokont Heterokonts are a group of protists (formally referred to as Heterokonta, Heterokontae or Heterokontophyta). The group is a major line of eukaryotes. Most are algae, ranging from the giant multicellular kelp to the unicellular diatoms, which ...

protist A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exc ...

s containing three diverse groups: the mostly

photosynthetic Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in c ...

Ochrophyta The ochrophytes, subphylum Ochrophytina, is a group of mostly photosynthetic heterokonts. Their plastid is of red algal origin. The classification of the group is still being worked out. Originally, the ochrophytes were regarded as a phylum den ...

, the parasitic

Pseudofungi Pseudofungi is a grouping of heterokonts, also known as the Heterokontimycotina. It consists of the Oomycota and Hyphochytridiomycetes. Although numerous biochemical, ultrastructural, and genetic traits clearly place them in the heterokonts, the ...

, and the recently described group of nanoflagellates known as

Bigyromonada Bigyromonadea is a recently described non-photosynthetic lineage of Heterokont Heterokonts are a group of protists (formally referred to as Heterokonta, Heterokontae or Heterokontophyta). The group is a major line of eukaryotes. Most are al ...

. Members of this phylum are characterized by the presence of a helix or a double helix/ring system in the ciliary transition region.

Phylogeny

Gyrista is the sister group to phylum

Bigyra Bigyra is a grouping of heterokont organisms. It includes Bicosoecida, Blastocystis and Labyrinthulida. It has also been described as containing Opalozoa, Bicoecia, and Sagenista. Phylogeny The cladogram below shows the internal relationship ...

, which contains the

Sagenista Sagenista is a group of heterokonts containing the labyrinthulids and Eogyrea, a class of yet uncultured protists. Originally, it contained the Labyrinthulids and bicosoecids. However at present the bicosoecids have been removed, and Eogyrea wer ...

and

Opalozoa Opalozoa is a subphylum of heterotrophic protists of the phylum Bigyra, and is the sister group to Sagenista. Opalozoans are non-photosynthetic heterokonts that are ancestrally phagotrophic but many times have evolved to be osmotrophic saprotrop ...

. Together, Gyrista and Bigyra form the superphylum

Stramenopiles Stramenopile is a clade of organisms 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 surface, and in some they have be ...

Heterokonta Heterokonts are a group of protists (formally referred to as Heterokonta, Heterokontae or Heterokontophyta). The group is a major line of eukaryotes. Most are algae, ranging from the giant multicellular kelp to the unicellular diatoms, which a ...

. A phylogenetic analysis in 2022 recovered a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

sister to

Classification

The 2018 revised taxonomy of Gyrista is the following, with the inclusion of new ochrophyte classes described in 2020 and 2021: *Subphylum

**Class

Developea Bigyromonadea is a recently described non- photosynthetic lineage of Heterokont Heterokonts are a group of protists (formally referred to as Heterokonta, Heterokontae or Heterokontophyta). The group is a major line of eukaryotes. Most are a ...

Bigyromonadea **Class

Pirsonea ''Pirsonia'' is a non photosynthetic genus of heterokonts. It comprises the entirety of the family Pirsoniaceae, order Pirsoniida and class Pirsonea in the subphylum Bigyromonada, phylum Gyrista Gyrista is a phylum of heterokont protists conta ...

*Subphylum

Heterokontimycotina **Class Hyphochytrea Hyphochytriomycota **Class

Oomycetes Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result ...

Oomycota ; Peronosporomycetes *Subphylum

Ochrophytina The ochrophytes, subphylum Ochrophytina, is a group of mostly photosynthetic heterokonts. Their plastid is of red algal origin. The classification of the group is still being worked out. Originally, the ochrophytes were regarded as a phylum de ...

Heterokontophyta ; Stramenochromes **Infraphylum

Chrysista The ochrophytes, subphylum Ochrophytina, is a group of mostly photosynthetic heterokonts. Their plastid is of red algal origin. The classification of the group is still being worked out. Originally, the ochrophytes were regarded as a phylum den ...

***Superclass Limnistia ****Class

Eustigmatophyceae Eustigmatophytes are a small group (17 genera; ~107 species) of eukaryotic forms of algae that includes marine, freshwater and soil-living species. All eustigmatophytes are unicellular, with coccoid cells and polysaccharide cell walls. Eus ...

****Class Chrysomonadea Chrysophyceae ****Class Picophagea Synchromophyceae_.html" ;"title="Synchromophyceae.html" ;"title="Synchromophyceae">Synchromophyceae ">Synchromophyceae.html" ;"title="Synchromophyceae">Synchromophyceae ***Superclass Raphidoistia ****Class Raphidomonadea *****Subclass Raphidophycidae *****Subclass Raphopoda ***Superclass Fucistia ****Class Aurophyceae *****Subclass Aurearenophycidae *****Subclass Phaeothamniophycidae ****Class

Chrysomerophyceae Chrysomerophyceae is a monotypic class of photosynthetic heterokont eukaryotes. Taxonomy * Class Chrysomerophyceae Cavalier-Smith 1995 ** Order Chrysomeridales O'Kelly & Billard ex Preisig *** Family Chrysomeridaceae Bourrelly 1957 **** Genu ...

****Class Chrysoparadoxophyceae ****Class Phaeosacciophyceae ****Class Schizocladiophyceae ****Class

Phaeophyceae Brown algae (singular: alga), comprising the class Phaeophyceae, are a large group of multicellular algae, including many seaweeds located in colder waters within the Northern Hemisphere. Brown algae are the major seaweeds of the temperate and po ...

Fucophyceae ; Melanophyceae *****Subclass

Discosporangiophycidae Discosporangiales is an order of brown algae Brown algae (singular: alga), comprising the class Phaeophyceae, are a large group of multicellular algae, including many seaweeds located in colder waters within the Northern Hemisphere. Brown alg ...

*****Subclass Ishigeophycidae *****Subclass Dictyotophycidae *****Subclass

Fucophycidae Fucophycidae is a subclass of Phaeophyceae (brown algae) which contains the most complex and evolved orders of Chromista algae. The members of this subclass have stalks with several morphological forms and distinct structures, characterized by ...

****Class

Xanthophyceae Yellow-green algae or the Xanthophyceae (xanthophytes) are an important group of heterokont algae. Most live in fresh water, but some are found in marine and soil habitats. They vary from single-celled flagellates to simple colonial and filamento ...

_Heterokontae_.html" ;"title="Tribophyceae ; Heterokontae ">Tribophyceae ; Heterokontae **Infraphylum Diatomista ***Superclass Hypogyrista ****Class

Dictyochophyceae Dictyochophyceae sensu lato is a photosynthetic lineage of heterokont algae. Taxonomy * Class Dictyochophyceae Silva 1980 s.l. ** Subclass Sulcophycidae Cavalier-Smith 2013 *** Order Olisthodiscales Cavalier-Smith 2013 **** Family Olisthodiscac ...

Dictyochia ; Alophycidae *****Subclass

Pedinellia The axodines are a group of unicellular stramenopiles that includes silicoflagellate and rhizochromulinid algae, actinomonad heterotrophic flagellates and actinophryid heliozoa. Alternative classifications treat the dictyochophytes as heterokont ...

Actinochrysophyceae ; Axodines*****Subclass Pelagophycidae *****?Subclass Sulcophycidae – ?'' Sulcochrysis'' ****Class

Pinguiophyceae Pinguiochrysidaceae is a family of marine Heterokontophyta. It is the only family in the order Pinguiochrysidales, which is the only order in the class Pinguiophyceae. It includes five species of unicellular organisms with high concentration of p ...

***Superclass

Khakista The ochrophytes, subphylum Ochrophytina, is a group of mostly photosynthetic heterokonts. Their plastid is of red algal origin. The classification of the group is still being worked out. Originally, the ochrophytes were regarded as a phylum den ...

****Class

Bolidophyceae Bolidophyceae is a class of photosynthetic heterokont picophytoplankton, and consist of less than 20 known species. They are distinguished by the angle of flagellar insertion and swimming patterns as well as recent molecular analyses. Bolidophyce ...

****Class Diatomeae

Bacillariophyceae Bacillariophyceae is a group of pennate diatoms with a raphe (raphids). According to Ruggiero et al., 2015, the diatoms are treated as follows. This treatment largely reflects that used by Algaebase as at 2015, and is also reflected in the current ...

*****Subclass Corethrophycidae *****Subclass

Rhizosoleniophycidae Rhizosoleniophycidae or Rhizosoleniineae is a grouping of centric diatoms. See also * Coscinodiscineae References SAR supergroup suborders Coscinodiscophyceae {{Diatom-stub ...

*****Subclass Eucentricophycidae *****Subclass Bacillariophycidae Pennatia ; =Pennatophycidae**Ochrophytina incertae sedis ***Class Olisthodiscophyceae

Notes

References

{{Taxonbar, from=Q21446106 Heterokonts