Euglenozoa

The euglenozoa are a large group of flagellate Excavata. They include a variety of common free-living species, as well as a few important parasites, some of which infect humans. There are two main subgroups, the euglenids and kinetoplastids. Euglenozoa are unicellular, mostly around  in size, although some euglenids get up to  long.

Structure
Most euglenozoa have two flagella, which are inserted parallel to one another in an apical or subapical pocket. In some these are associated with a cytostome or mouth, used to ingest bacteria or other small organisms. This is supported by one of three sets of microtubules that arise from the flagellar bases; the other two support the dorsal and ventral surfaces of the cell.

Some other euglenozoa feed through absorption, and many euglenids possess chloroplasts, the only eukaryotes outside Diaphoretickes to do so without performing kleptoplasty, and so obtain energy through photosynthesis. These chloroplasts are surrounded by three membranes and contain chlorophylls A and B, along with other pigments, so are probably derived from a captured green alga.  Reproduction occurs exclusively through cell division.  During mitosis, the nuclear membrane remains intact, and the spindle microtubules form inside of it.

The group is characterized by the ultrastructure of the flagella.  In addition to the normal supporting microtubules or axoneme, each contains a rod (called paraxonemal), which has a tubular structure in one flagellum and a latticed structure in the other.  Based on this, two smaller groups have been included here: the diplonemids and Postgaardi.

Classification
The euglenozoa are generally accepted as monophyletic. They are related to Percolozoa; the two share mitochondria with disk-shaped cristae, which only occurs in a few other groups.
Both probably belong to a larger group of eukaryotes called the Excavata. This grouping, though, has been challenged.

Phylogeny
The phylogeny based on the work of Cavalier-Smith 2016.

Taxonomy
Phylum Euglenozoa Cavalier-Smith 1981 emend. Simpson 1997 [Euglenobionta]
 Subphylum Glycomonada Cavalier-Smith 2016
 Class Diplonemea Cavalier-Smith 1993 emend. Simpson 1997 [Diplosonematea; Diplonemia Cavalier-Smith 1993]
 Order Diplonemida Cavalier-Smith 1993 [Hemistasiida]
 Family Hemistasiidae Cavalier-Smith 2016 [Entomosigmaceae]
 Family Eupelagonemidae Okamoto & Keeling 2018
 Family Diplonemidae Cavalier-Smith 1993 [Rhynchopodaceae Skuja 1948 ex Cavalier-Smith 1993]
 Class Kinetoplastea Honigberg 1963 emend. Margulis 1974 [Kinetoplastida Honigberg 1963; Kinetoplasta Honigberg 1963 stat. nov.]
 Family ?Cephalothamniidae
 Order ?Bordnamonadida
 Family Bordnamonadidae Cavalier-Smith 2013
 Order ?Trypanophidida
 Family Trypanophididae Poche 1911
 Subclass Prokinetoplastina Vickerman 2004
 Order Prokinetoplastida Vickerman 2004
 Family Ichthyobodonidae Isaksen et al., 2007
 Subclass Metakinetoplastina Vickerman 2004
 Order Neobodonida Vickerman 2004
 Family Rhynchomonadidae Cavalier-Smith 2016
 Family Neobodonidae Cavalier-Smith 2016
 Order Parabodonida Vickerman 2004
 Family Parabodonidae Cavalier-Smith 2016 [Cryptobiaceae Poche 1911; Trypanoplasmatidae Hartmann & Chagas 1910]
 Order Bodonida Hollande 1952 emend. Vickerman 1976 [Eubodonida Vickerman 2004]
 Family Bodonidae Bütschli 1883 [Bodonaceae Lemmermann 1914; Bodoninae Bütschli 1883; Pleuromonadidae Kent 1880]
 Order Trypanosomatida Kent 1880 stat. n. Hollande, 1952 emend. Vickerman 2004
 Family Trypanosomatidae Doflein 1901
 Subphylum Plicomonada Cavalier-Smith 2017
 Infraphylum Postgaardia Cavalier-Smith 2016 stat. nov. Cavalier-Smith 2017
 Class Postgaardea Cavalier-Smith 1998 s.s. [Symbiontida Yubuki et al., 2009]
 Order Bihospitida Cavalier-Smith 2016
 Family Bihospitidae Cavalier-Smith 2016
 Order Postgaardida Cavalier-Smith 2003
 Family Calkinsiidae Cavalier-Smith 2016
 Family Postgaardidae Cavalier-Smith 2016
 Infraphylum Euglenoida Bütschli 1884 emend. Senn 1900 stat. nov. Cavalier-Smith, 2017 [Euglenophyta; Euglenida Buetschli 1884; Euglenoidina Buetschli 1884]
 Parvphylum Entosiphona Cavalier-Smith 2016 stat. nov. Cavalier-Smith 2017
 Class Entosiphonea Cavalier-Smith 2016
 Order Entosiphonida Cavalier-Smith 2016
 Family Entosiphonidae Cavalier-Smith 2016
 Parvphylum Dipilida Cavalier-Smith 2016 stat. nov. Cavalier-Smith 2017
 Class Stavomonadea Cavalier-Smith 2016 [Petalomonadea Cavalier-Smith 1993; Petalomonadophyceae]
 Subclass Heterostavia Cavalier-Smith 2016
 Order Heterostavida Cavalier-Smith 2016
 Family Serpenomonadidae Cavalier-Smith 2016
 Subclass Homostavia Cavalier-Smith 2016
 Order Decastavida Cavalier-Smith 2016a
 Family Decastavidae Cavalier-Smith 2016a
 Family Keelungiidae Cavalier-Smith 2016a
 Order Petalomonadida Cavalier-Smith 1993 [Sphenomonadales Leedale 1967; Sphenomonadina Leedale 1967]
 Family Sphenomonadidae Kent 1880
 Family Petalomonadidae [Petalomonadaceae Buetschli 1884; Notosolenaceae Stokes 1888; Scytomonadaceae Ritter von Stein 1878]
 Class Ploeotarea Cavalier-Smith 2016
 Order Ploeotiida Cavalier-Smith 1993
 Family Lentomonadidae Cavalier-Smith 2016
 Family Ploeotiidae Cavalier-Smith 2016
 Superclass Spirocuta Cavalier-Smith 2016
 Class Peranemea Cavalier-Smith 1993 emend. Cavalier-Smith 2016
 Subclass Acroglissia Cavalier-Smith 2016
 Order Acroglissida Cavalier-Smith 2016
 Family Teloproctidae Cavalier-Smith 2016a
 Subclass Peranemia Cavalier-Smith 2016
 Order Peranemida Bütschli 1884 stat. nov. Cavalier-Smith 1993
 Family Peranematidae [Peranemataceae Dujardin 1841; Pseudoperanemataceae Christen 1962]
 Subclass Anisonemia Cavalier-Smith 2016
 Order Anisonemida Cavalier-Smith 2016 [Heteronematales Leedale 1967]
 Family Anisonemidae Saville Kent, 1880 em. Cavalier-Smith 2016 [Heteronemidae Calkins 1926; Zygoselmidaceae Kent 188]
 Order Natomonadida Cavalier-Smith 2016
 Suborder Metanemina Cavalier-Smith 2016
 Family Neometanemidae Cavalier-Smith 2016
 Suborder Rhabdomonadina Leedale 1967 emend. Cavalier-Smith 1993 [Astasida Ehrenberg 1831; Rhabdomonadia Cavalier-Smith 1993; Rhabdomonadophyceae; Rhabdomonadales]
 Family Distigmidae Hollande, 1942
 Family Astasiidae Saville Kent, 1884 [Astasiaceae Ehrenberg orth. mut. Senn 1900; Rhabdomonadaceae Fott 1971; Menoidiaceae Buetschli 188; Menoidiidae Hollande, 1942]
 Class Euglenophyceae Schoenichen 1925 emend. Marin & Melkonian 2003 [Euglenea Bütschli 1884 emend. Busse & Preisfeld 2002; Euglenoidea Bütschli 1884; Euglenida Bütschli 1884] (Photosynthetic clade)
 Subclass Rapazia Cavalier-Smith 2016
 Order Rapazida Cavalier-Smith 2016
 Family Rapazidae Cavalier-Smith 2016
 Subclass Euglenophycidae Busse and Preisfeld, 2003
 Order Eutreptiida [Eutreptiales Leedale 1967 emend. Marin & Melkonian 2003; Eutreptiina Leedale 1967]
 Family Eutreptiaceae [Eutreptiaceae Hollande 1942]
 Order Euglenida Ritter von Stein, 1878 stat. n. Calkins, 1926 [Euglenales Engler 1898 emend. Marin & Melkonian 2003; Euglenina Buetschli 1884; Euglenomorphales Leedale 1967; Colaciales Smith 1938]
 Family Euglenamorphidae Hollande, 1952 stat. n. Cavalier-Smith 2016 [Euglenomorphaceae; Hegneriaceae Brumpt & Lavier 1924]
 Family Phacidae [Phacaceae Kim et al. 2010]
 Family Euglenidae Bütschli 1884 [Euglenaceae Dujardin 1841 emend. Kim et al. 2010; Colaciaceae Smith 1933] (Mucilaginous clade)

References

External links
Tree of Life: Euglenozoa

 
Category:Bikont phyla
Category:Taxa named by Thomas Cavalier-Smith