Editing Percolozoa

{{short description|Phylum of excavates}}
{{Automatic taxobox
| image = Naegleria (formes) en.png
| image_caption = The three different stages of ''[[Naegleria fowleri|N. fowleri]]''
| taxon = Percolozoa
| display_parents = 4
| authority = [[Thomas Cavalier-Smith|Cavalier-Smith]] 1991
| subdivision_ranks = Classes
| subdivision = 
* [[Heterolobosea]]
* [[Lunosea]]
* [[Lyromonadea]]
* [[Neovahlkampfea]]
* [[Pharyngomonadea]]
|synonyms =
* Acrasiomycota <small>Whittaker 1969</small>
* Amoeboflagellates 
* Pseudociliata <small>Cavalier-Smith 1993</small>
* Schizopyrenia
* Tetramitozoa <small>Dillon 1963</small>
* Stephanopogonophyta <small>Doweld 2001</small>
* Stephanopogonomorpha <small>Sleigh et al. 1984</small>
}}

The '''Percolozoa''' are a group of colourless, non-photosynthetic [[Excavata|excavates]], including many that can transform between [[amoeboid]], [[flagellate]], and [[microbial cyst|cyst]] stages.

==Characteristics==
Most Percolozoa are found as bacterivores in soil, fresh water and occasionally in the ocean.<ref>{{Citation |last=Esteban |first=Genoveva F. |title=Free-Living Protozoa |date=2015 |work=Thorp and Covich's Freshwater Invertebrates |pages=122 |url=https://linkinghub.elsevier.com/retrieve/pii/B9780123850263000073 |access-date=2024-12-14 |publisher=Elsevier |language=en |doi=10.1016/b978-0-12-385026-3.00007-3 |isbn=978-0-12-385026-3 |last2=Finlay |first2=Bland J. |last3=Warren |first3=Alan}}</ref> The only member of this group that is infectious to humans is ''[[Naegleria fowleri]]'', the causative agent of the often fatal disease [[amoebic meningitis]].<ref name=":0">{{Citation |last=Pánek |first=Tomáš |title=Heterolobosea |date=2016 |work=Handbook of the Protists |pages=1–42 |editor-last=Archibald |editor-first=John M. |url=http://link.springer.com/10.1007/978-3-319-32669-6_10-1 |access-date=2024-12-14 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-319-32669-6_10-1 |isbn=978-3-319-32669-6 |last2=Simpson |first2=Alastair G. B. |last3=Brown |first3=Matthew W. |last4=Dexter Dyer |first4=Betsey |editor2-last=Simpson |editor2-first=Alastair G.B. |editor3-last=Slamovits |editor3-first=Claudio H. |editor4-last=Margulis |editor4-first=Lynn}}</ref> The group is closely related to the [[Euglenozoa]], and share with them the unusual characteristic of having [[mitochondrion|mitochondria]] with discoid [[crista]]e.<ref name="pmid14657102" /> The presence of a ventral feeding groove in the flagellate stage, as well as other features, suggests that they are part of the [[Excavata]] group.<ref name="CavSmith 2021" />

The amoeboid stage is roughly cylindrical, typically around [[1 E-5 m|20–40 μm]] in length. They are traditionally considered lobose amoebae, but are not related to the others, and unlike them, do not form true lobose [[pseudopods]].  Instead, they advance by eruptive waves, where hemispherical bulges appear from the front margin of the cell, which is clear. The flagellate stage is slightly smaller, with two or four anterior flagella anterior to the feeding groove.<ref name=":0" />

Usually, the amoeboid form is taken when food is plentiful, and the flagellate form is used for rapid locomotion. However, not all members are able to assume both forms. The genera ''[[Percolomonas]]'', ''[[Lyromonas]]'', and ''[[Psalteriomonas]]'' are known only as flagellates, while ''[[Vahlkampfia]]'', ''[[Pseudovahlkampfia]]'', and most [[acrasid]]s do not have flagellate stages. As mentioned above, under unfavourable conditions, the acrasids aggregate to form sporangia. These are superficially similar to the sporangia of the [[dictyostelid]]s, but the amoebae only aggregate as individuals or in small groups and do not die to form the stalk.<ref name=":0" />

[[File:2023 Heterolobosean.svg|center|thumb|upright=2|{{center|'''Representation of a heterolobosean'''}}]]

==Terminology and classification==
These are collectively referred to as schizopyrenids, amoeboflagellates, or vahlkampfids.  They also include the acrasids, a group of social amoebae that aggregate to form [[sporangium|sporangia]].  The entire group is usually called the '''Heterolobosea''', but this may be restricted to members with amoeboid stages.

One Heterolobosea classification system is:<ref name=":0" />
* Order [[Schizopyrenida]]
** Family [[Vahlkampfiidae]]
** Family [[Gruberellidae]]
* Order [[Acrasida]]
** Family [[Acrasidae]]
''Pleurostomum flabellatum'' has recently been added to Heterolobosea.<ref name="pmid17576098">{{cite journal |vauthors=Park JS, Simpson AG, Lee WJ, Cho BC |title=Ultrastructure and phylogenetic placement within Heterolobosea of the previously unclassified, extremely halophilic heterotrophic flagellate ''Pleurostomum flabellatum'' (Ruinen 1938) |journal=Protist |volume=158 |issue=3 |pages=397–413 |date=July 2007 |pmid=17576098 |doi=10.1016/j.protis.2007.03.004 }}</ref>

===Phylogeny===
Based on the cladogram from Tolweb and updated by Pánek and Čepička 2014.<ref>{{cite journal|title=Survey on diversity of marine/saline anaerobic Heterolobosea (Excavata: Discoba) with description of seven new species |journal=International Journal of Systematic and Evolutionary Microbiology |volume=64|issue= Pt 7|pages=2280–2304 |doi=10.1099/ijs.0.063487-0 |date=2014 |pmid=24729392|doi-access=free |last1=Pánek |first1=Tomáš |last2=Ptáčková |first2=Eliška |last3=Čepička |first3=Ivan }}</ref><ref name="CavSmith 2021">{{cite journal|vauthors=Cavalier-Smith T|title=Ciliary transition zone evolution and the root of the eukaryote tree: implications for opisthokont origin and classification of kingdoms Protozoa, Plantae, and Fungi|journal=Protoplasma|doi=10.1007/s00709-021-01665-7|date=December 2021|volume=259|issue=3 |pages=487–593|pmid=34940909 |pmc=9010356}}</ref>

{{clade| style=font-size:90%;line-height:80%
|1={{Clade
  |label1=Pharyngomonada
  |1={{Clade
    |label1=Pharyngomonadea
    |1={{Clade
      |label1=Pharyngomonadida
      |1={{Clade
        |label1=Pharyngomonadidae
        |1=''[[Pharyngomonas]]''
         }}
       }}
     }}
  |label2=Tetramitia
  |2={{Clade
    |1={{Clade
    |label1=Lunosea
    |1={{Clade
      |label1=Selenaionida
      |1={{Clade
        |label1=Selenaionidae
        |1={{Clade
          |1=''[[Selenaion]]''
          |2=''[[Dactylomonas]]''
           }}
         }}
       }}
       }}
    |2={{Clade
      |label1=Neovahlkampfea
      |1={{Clade
        |label1=Neovahlkampfida 
        |1={{Clade
          |label1=Neovahlkampfiidae
          |1=''[[Neovahlkampfia]]''
           }}
         }}
      |label2=Eutetramitia
      |2={{Clade
        |label1=Lyromonadea
        |1={{Clade
          |label1=Lyromonadida
          |1={{Clade
            |1={{Clade
              |label1=Plaesiobystridae
              |1={{Clade
                |1=''[[Euplaesiobystra]]''
                |2=''[[Heteramoeba]]''
                 }}
              |label2=[[Gruberellidae]]
              |2={{Clade
                |1=''[[Vrihiamoeba]]''
                |2={{Clade
                  |1=''[[Oramoeba]]''
                  |2=''[[Stachyamoeba]]''
                   }}
                 }}
               }}
            |2={{Clade
              |label1=Paravahlkampfiidae
              |1={{Clade
                |1={{Clade
                  |1=''[[Fumarolamoeba]]''
                  |2=''[[Parafumarolamoeba]]''
                   }}
                |2=''[[Paravahlkampfia]]''
                 }}
              |label2=Psalteriomonadidae
              |2={{Clade
                |1={{Clade
                  |1=''[[Sawyeria]]''
                  |2=''[[Psalteriomonas]]''
                   }}
                |2={{Clade
                  |1=''[[Pseudoharpagon]]''
                  |2={{Clade
                    |1=''[[Pseudomastigamoeba]]''
                    |2={{Clade
                      |1=''[[Harpagon]]''
                      |2=''[[Monopylocystis]]''
                       }}
                     }}
                   }}
                 }}
               }}
             }}
           }}
        |label2=[[Heterolobosea]]
        |2={{Clade
          |label1=[[Acrasida]]
          |1={{Clade
            |label1=[[Acrasidae]]
            |1={{Clade
              |1={{Clade
                |1=''[[Allovahlkampfia]]''
                |2=''[[Solumitrus]]''
                 }}
              |2={{Clade
                |1=''[[Pocheina]]''
                |2=''[[Acrasis]]''
                 }}
               }}
             }}
          |label2=Amoebomastigota
          |2={{Clade
            |1={{Clade
            |label1=Naegleriida
            |1={{Clade
              |1=''[[Marinamoeba]]''
              |2={{Clade
                |label1=Tulamoebidae
                |1={{Clade
                  |1=''[[Pleurostomum]]''
                  |2=''[[Tulamoeba]]''
                   }}
                |label2=Naegleriidae
                |2={{Clade
                  |1=''[[Naegleria]]''
                  |2=''[[Willaertia]]''
                   }}
                 }}
               }}
               }}
            |2={{Clade
              |1={{Clade
              |label1=Vahlkampfiida s.s.
              |1={{Clade
                |label1=[[Vahlkampfiidae]]
                |1={{Clade
                  |1=''[[Tetramitus]]''
                  |2=''[[Vahlkampfia]]''
                   }}
                 }}
                 }}
              |2={{Clade
                |label1=Creneida
                |1={{Clade
                  |label1=Creneidae
                  |1=''[[Creneis (genus)|Creneis]]''
                   }}
                |label2=[[Percolatea|Percolomonadida]]<ref name="Hohlfeld_2023"/>
                |2={{Clade
                  |1={{Clade
                  |label1=[[Stephanopogonidae]]
                  |1=''[[Stephanopogon]]''
                     }}
                  |2={{Clade
                    |1={{Clade
                    |label1=Barbellidae
                    |1={{Clade
                      |1=''[[Barbelia]]''
                      |2=''[[Nonamonas]]''
                       }}
                       }}
                    |2={{Clade
                      |label1=Lulaidae
                      |1=''[[Lula (protist)|Lula]]''
                      |label2=Percolomonadidae
                      |2={{Clade
                        |1=''[[Percolomonas]]''
                        |2=''[[Nakurumonas]]''
                         }}
                       }}
                     }}
                   }}
                 }}
               }}
             }}
           }}
         }}
       }}
     }}
   }}
}}

===Taxonomy===
Phylum Percolozoa <small>Cavalier-Smith 1991</small><ref>{{cite journal | website=Collection of genus-group names in a systematic arrangement | title=Part 1- Virae, Prokarya, Protists, Fungi | url=http://mave.tweakdsl.nl/tn/genera1.html | display-authors=etal | access-date=30 June 2016 | archive-url=https://web.archive.org/web/20160814234049/http://mave.tweakdsl.nl/tn/genera1.html | archive-date=14 August 2016 | url-status=dead }}</ref>
* Subphylum Pharyngomonada <small>Cavalier-Smith 1991</small>
** Class Pharyngomonadea <small>Cavalier-Smith 2008</small> [Macropharyngomonadidea]
*** Order Pharyngomonadida <small>Cavalier-Smith 2008</small> [Macropharyngomonadida]
**** Family Pharyngomonadidae <small>Cavalier-Smith 2008</small> [Macropharyngomonadidae <small>Cavalier-Smith 2008</small>]
***** Genus ''[[Pharyngomonas]]''  <small>Cavalier-Smith 2008</small> [''Macropharyngomonas'' nomen nudum]
* Subphylum Tetramitia <small>Cavalier-Smith 1993 em. Cavalier-Smith 2008</small>
** Genus ?''[[Costiopsis]]'' <small>Senn 1900</small>
** Genus ?''[[Hoehnemastix]]'' <small>Skvortzov 1974</small>
** Genus ?''[[Planiosculum]]'' <small>Szabados 1948</small>
** Genus ?''[[Protomyxomyces]]'' <small>Cunningham 1881</small>
** Genus ?''[[Protonaegleria]]'' <small>Michel & Raether 1985</small>
** Genus ?''[[Pseudovahlkampfia]]'' <small>Sawyer 1980</small>
** Genus ?''[[Schizamoeba]]'' <small>Davis 1926</small>
** Genus ?''[[Tetramastigamoeba]]'' <small>Singh & Hanumaiah 1977</small>
** Genus ?''[[Trimastigamoeba]]'' <small>Whitmore 1911</small>
** Genus ?''[[Wasielewskia]]'' <small>Hartmann & Schuessler 1913</small>
** Family Euhyperamoebidae <small>Goodkov & Seravin 1984</small> [Hyperamoebidae <small>Goodkov, Seravin & Railkin 1982</small>]
*** Genus ''[[Euhyperamoeba]]'' <small>Goodkov & Seravin 1984</small> [''[[Hyperamoeba]]'' <small>Goodkov, Seravin & Railkin 1982 non Alexeieff 1923</small>]
** Class Lunosea <small>Cavalier-Smith 2021</small>
*** Order Selenaionida <small>Hanousková, Táborský & Čepička 2018</small>
**** Family Selenaionidae <small>Hanousková, Táborský & Čepička 2018</small>
***** Genus ''[[Selenaion]]'' <small>Park, De Jonckheere & Simpson 2012</small>
***** Genus ''[[Dactylomonas]]'' <small>Hanousková, Táborský & Čepička 2018</small>
** Class Neovahlkampfiea <small>Cavalier-Smith 2021</small>
*** Order Neovahlkampfiida <small>Cavalier-Smith 2021</small>
**** Family Neovahlkampfiidae <small>Hanousková, Táborský & Čepička 2018</small>
***** Genus ''[[Neovahlkampfia]]'' <small>Brown & de Jonckheere 1999</small>
** Class Lyromonadea <small>Cavalier-Smith 1993</small>
*** Order Lyromonadida <small>Cavalier-Smith 1993</small>
**** Family [[Gruberellidae]] <small>Page & Blanton 1985</small>
***** Genus ''[[Gruberella]]'' <small>Page 1984 non Gruber 1889 non Corliss 1960</small>
***** Genus ''[[Oramoeba]]'' <small>de Jonckheere et al. 2011</small>
***** Genus ''[[Stachyamoeba]]'' <small>Page 1975</small>
***** Genus ''[[Vrihiamoeba]]'' <small>Murase, Kawasak & Jonckheere 2010</small>
**** Family Paravahlkampfiidae
***** Genus ''[[Fumarolamoeba]]'' <small>De Jonckheere, Murase & Opperdoes 2011</small>
***** Genus ''[[Parafumarolamoeba]]'' <small>Geisen et al. 2015</small>
***** Genus ''[[Paravahlkampfia]]'' <small>Brown & de Jonckheere 1999</small>
**** Family Plaesiobystridae
***** Genus ''[[Euplaesiobystra]]'' <small>Park et al. 2009</small>
***** Genus ''[[Heteramoeba]]'' <small>Droop 1962</small>
***** Genus ''[[Pernina]]'' <small>El Kadiri, Joyon & Pussard 1992</small>
**** Family Psalteriomonadidae <small>Cavalier-Smith 1993</small> [Lyromonadidae <small>Cavalier-Smith 1993</small>]
***** Genus ''[[Harpagon]]'' <small>Pánek et al. 2012</small>
***** Genus ''[[Monopylocystis]]'' <small>O'Kelly et al. 2003</small>
***** Genus ''[[Psalteriomonas]]'' <small>Broers et al. 1990</small> [''[[Lyromonas]]'' <small>Cavalier-Smith 1993</small>]
***** Genus ''[[Pseudoharpagon]]'' <small>Pánek et al. 2012</small>
***** Genus ''[[Pseudomastigamoeba]]''
***** Genus ''[[Sawyeria]]'' <small>O'Kelly et al. 2003</small>
** Class [[Heterolobosea]] <small>Page & Blanton 1985</small>
*** Order [[Acrasida]] <small>Schröter 1886</small>
**** Family [[Acrasidae]] <small>van Tieghem 1880 ex Hartog 1906</small>
***** Genus ''[[Acrasis]]'' <small>van Tieghem 1880</small>
***** Genus ''[[Allovahlkampfia]]'' <small>Walochnik & Mulec 2009</small>
***** Genus ''[[Pocheina]]'' <small>Loeblich & Tappan 1961</small> [''[[Guttulina]]'' <small>Cienkowski 1873 non D'Orbigny 1839</small>]
***** Genus ''[[Solumitrus]]'' <small>Wang et al. 2011</small>
*** Order Naegleriida <small>Starobogatov 1980</small>
**** Genus ''[[Marinamoeba]]'' <small>De Jonckheere et al. 2009</small>
**** Family Tulamoebidae <small>Kirby et al. 2015</small>
***** Genus ''[[Aurem]]'' <small>Jhin & Park 2018</small>
***** Genus ''[[Pleurostomum]]'' <small>Namyslowski 1913</small>
***** Genus ''[[Tulamoeba]]'' <small>Park et al. 2009</small>
**** Family Naegleriidae <small>Kudo 1954</small> [Schizopyrenidae <small>Singh 1951 ex Singh 1952</small>; Bistadiidae <small>Doflein 1916</small>]
***** Genus ''[[Naegleria]]'' <small>Aléxéieff 1912</small> [''[[Adelphamoeba]]'' <small>Napolitano, Wall & Ganz 1970</small>; ''Didascalus'' <small>Singh 1952</small>; ''Schizopyrenus'' <small>Singh 1951 ex Singh 1952</small>]
***** Genus ''[[Willaertia]]'' <small>de Jonckheere et al. 1984</small>
*** Order Tetramitida <small>Doweld 2001</small>
**** Family [[Vahlkampfiidae]] <small>Jollos 1917 s.s.</small>
***** Genus ''[[Tetramitus]]'' <small>Perty 1852</small> [''Copromastix'' <small>Aragao 1916</small>; ''[[Learamoeba]]'' <small>Sawyer et al. 1998</small>, ''[[Paratetramitus]]'' <small>Darbyshire, Page & Goodfellow 1976</small>, ''Singhamoeba'' <small>Sawyer, Nerad & Munson 1992</small>]
***** Genus ''[[Vahlkampfia]]'' <small>Chatton & LaLung-Bonnaire 1912</small> [''Guttulidium'' <small>Frenzel 1892</small>]
*** Order Creneida <small>Cavalier-Smith 2021</small>
**** Family Creneidae <small>Pánek et al. 2014</small>
***** Genus ''[[Creneis (genus)|Creneis]]'' <small>Pánek et al. 2014</small>
*** Order Percolomonadida <small>Cavalier-Smith 1993</small>
**** Family Barbeliidae <small>Arndt 2023</small><ref name="Hohlfeld_2023">{{cite journal |last1=Hohlfeld |first1=Manon |last2=Meyer |first2=Claudia |last3=Schoenle |first3=Alexandra |last4=Nitsche |first4=Frank |last5=Arndt |first5=Hartmut |title=Biogeography, autecology, and phylogeny of Percolomonads based on newly described species |journal=Journal of Eukaryotic Microbiology |date=January 2023 |volume=70 |issue=1 |pages=e12930 |doi=10.1111/jeu.12930 |pmid=35712988|doi-access=free }}</ref>
***** Genus ''[[Barbelia]]'' <small>Arndt 2021</small> 
***** Genus ''[[Nonamonas]]'' <small>Hohlfeld, Meyer & Arndt 2023</small> 
**** Family Lulidae <small>Hohlfeld & Arndt 2023</small><ref name="Hohlfeld_2023"/>
***** Genus ''[[Lula (protist)|Lula]]'' <small>Arndt, Nitsche & Carduck 2021</small> 
**** Family [[Percolomonadidae]] <small>Cavalier-Smith 1993</small> [Choanogasteraceae]
***** Genus ''[[Percolomonas]]'' <small>Fenchel & Patterson 1986</small> [''Choanogaster'' <small>Pochmann 1959</small>]
**** Family [[Stephanopogonidae]] <small>Corliss 1961</small>
***** Genus ''[[Nakurumonas]]'' <small>Carduck, Nitsche & Arndt 2021</small>
***** Genus ''[[Stephanopogon]]'' <small>Entz 1884</small>

==History==
The Heterolobosea were first defined by [[F. C. Page|Page]] and [[R. L. Blanton|Blanton]] in 1985<ref>
{{cite journal
 | last = Page | first =  F.C.
 |author2=R.L. Blanton
 | title = The Heterolobosea (Sarcodina: Rhizopoda), a new class uniting the Schizopyrenida and Acrasidae (Acrasida)
 | journal = Protistologica
 | year = 1985 | volume = 21 | pages = 121–132
 }}
</ref> as a class of amoebae, and so only included those forms with amoeboid stages.  [[Thomas Cavalier-Smith|Cavalier-Smith]] created the phylum Percolozoa for the extended group, together with the enigmatic flagellate ''[[Stephanopogon]]''.<ref>{{cite book
 | last = Cavalier-Smith | first = T.
 | year = 1991
 | chapter = Cell diversification in heterotrophic flagellates
 | title = The Biology of Free-living Heterotrophic Flagellates
 | editor = D.J. Patterson & J. Larsen
 | pages = 113–131 | isbn =9780198577478
 | publisher = Oxford University Press
 }}
</ref>

Cavalier-Smith maintained the Heterolobosea as a class for amoeboid forms. He has defined Percolozoa as "Heterolobosea plus [[Percolatea]] classis nov."<ref name="pmid14657102">{{cite journal |author=Cavalier-Smith T |title=The excavate protozoan phyla Metamonada Grassé emend. (Anaeromonadea, Parabasalia, Carpediemonas, Eopharyngia) and Loukozoa emend. (Jakobea, Malawimonas): their evolutionary affinities and new higher taxa |journal=Int. J. Syst. Evol. Microbiol. |volume=53 |issue=Pt 6 |pages=1741–58 |date=November 2003 |pmid=14657102 |doi= 10.1099/ijs.0.02548-0|doi-access=free }}</ref>

==References==
{{Reflist}}

==External links==
* [http://tolweb.org/Heterolobosea/96360 Tree of Life Heterolobosea]

{{Eukaryota classification}}
{{Excavata}}
{{Taxonbar|from=Q22094454}}
[[Category:Percolozoa| ]]
[[Category:Discoba phyla]]
[[Category:Taxa named by Thomas Cavalier-Smith]]