Obazoa

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Obazoa
Temporal range: Late Stenian - Present, 1031.4–0 Ma
Cronoflagelado2.svg
Scheme of a choanoflagellate cell
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Clade: Amorphea
Clade: Obazoa
Brown, 2013
Clades

sister: Amoebozoa

Obazoa is a proposed sister clade of Amoebozoa (which together form Amorphea). The term Obazoa is based on the OBA acronym for Opisthokonta, Breviatea, and Apusomonadida, the group's three constituent clades. [1]

Determining the placement of Breviatea and Apusomonadida and their properties is of interest for the development of the opisthokonts in which the main lineages of animals and fungi emerged. [1] The relationships among opisthokonts, breviates and apusomonads are not conclusively resolved (as of 2018), though Breviatea is usually inferred to be the most basal of the three lineages. [2] [3] [4] [5] [6]

The phylogeny of the Obazoa is shown in the cladogram. [6] [7] [8] [9]

Eukaryotes
Diphoda

Diaphoretickes (inc. plants)

Discoba

Bikonts

Ancyromonadida

Malawimonada

CRuMs

Amorphea

Amoebozoa

Obazoa

Breviatea

Apusomonadida

Opisthokonta

Holomycota (inc. fungi)

Holozoa (inc. animals)

1300 mya
1500 mya
2200 mya

Related Research Articles

<span class="mw-page-title-main">Excavata</span> Supergroup of unicellular organisms belonging to the domain Eukaryota

Excavata is an extensive and diverse but paraphyletic group of unicellular Eukaryota. The group was first suggested by Simpson and Patterson in 1999 and the name latinized and assigned a rank by Thomas Cavalier-Smith in 2002. It contains a variety of free-living and symbiotic protists, and includes some important parasites of humans such as Giardia and Trichomonas. Excavates were formerly considered to be included in the now obsolete Protista kingdom. They were distinguished from other lineages based on electron-microscopic information about how the cells are arranged. They are considered to be a basal flagellate lineage.

<span class="mw-page-title-main">Opisthokont</span> Group of eukaryotes which includes animals and fungi, among other groups

The opisthokonts are a broad group of eukaryotes, including both the animal and fungus kingdoms. The opisthokonts, previously called the "Fungi/Metazoa group", are generally recognized as a clade. Opisthokonts together with Apusomonadida and Breviata comprise the larger clade Obazoa.

<span class="mw-page-title-main">Amorphea</span> Members of the Unikonta, a taxonomic group proposed by Thomas Cavalier-Smith

Amorphea is a taxonomic supergroup that includes the basal Amoebozoa and Obazoa. That latter contains the Opisthokonta, which includes the Fungi, Animals and the Choanomonada, or Choanoflagellates. The taxonomic affinities of the members of this clade were originally described and proposed by Thomas Cavalier-Smith in 2002.

<span class="mw-page-title-main">Apusozoa</span> Phylum of micro-organisms

The Apusozoa are a paraphyletic phylum of flagellate eukaryotes. They are usually around 5–20 μm in size, and occur in soils and aquatic habitats, where they feed on bacteria. They are grouped together based on the presence of an organic shell or theca under the dorsal surface of the cell.

<span class="mw-page-title-main">Malawimonadidae</span> Family of protists

Malawimonadidae is a family of unicellular eukaryotes of outsize importance in understanding eukaryote phylogeny.

<i>Breviata</i> Genus of flagellated amoebae

Breviata anathema is a single-celled flagellate amoeboid eukaryote, previously studied under the name Mastigamoeba invertens. The cell lacks mitochondria, much like the pelobionts to which the species was previously assigned, but has remnant mitochondrial genes, and possesses an organelle believed to be a modified anaerobic mitochondrion, similar to the mitosomes and hydrogenosomes found in other eukaryotes that live in low-oxygen environments.

<span class="mw-page-title-main">Loukozoa</span> Proposed taxon

Loukozoa is a proposed taxon used in some classifications of eukaryotes, consisting of the Metamonada and Malawimonadea. Ancyromonads are closely related to this group, as sister of the entire group, or as sister of the Metamonada. Amorphea may have emerged in this grouping, specifically as sister of the Malawimonads.

<span class="mw-page-title-main">SAR supergroup</span> Eukaryotes superphylum

SAR or Harosa is a highly diverse clade of eukaryotes, often considered a supergroup, that includes stramenopiles (heterokonts), alveolates, and rhizarians. It is a node-based taxon, including all descendants of the three groups' last common ancestor, and comprises most of the now-rejected Chromalveolata. Their sister group has been found to be telonemids, with which they make up the TSAR clade.

<span class="mw-page-title-main">Apusomonadidae</span> Group of microorganisms with two flagella

The apusomonads are a group of protozoan zooflagellates that glide on surfaces, and mostly consume prokaryotes. They are of particular evolutionary interest because they appear to be the sister group to the Opisthokonts, the clade that includes both animals and fungi. Together with the Breviatea, these form the Obazoa clade.

<span class="mw-page-title-main">Ancyromonadida</span> Group of protists

Ancyromonadida or Planomonadida is a small group of biflagellated protists found in the soil and in aquatic habitats, where they feed on bacteria. Includes freshwater or marine organisms, benthic, dorsoventrally compressed and with two unequal flagellae, each emerging from a separate pocket. The apical anterior flagellum can be very thin or end in the cell membrane, while the posterior flagellum is long and is inserted ventrally or laterally. The cell membrane is supported by a thin single-layered theca and the mitochondrial crests are discoidal/flat.

<span class="mw-page-title-main">Diaphoretickes</span> Taxon of eukaryotes

Diaphoretickes is a major group of eukaryotic organisms, with over 400,000 species. The majority of the earth's biomass that carries out photosynthesis belongs to Diaphoretickes.

<span class="mw-page-title-main">Breviatea</span> Group of protists

Breviatea, commonly known as breviate amoebae, are a group of free-living, amitochondriate protists with uncertain phylogenetic position. They are biflagellate, and can live in anaerobic (oxygen-free) environments. They are currently placed in the Obazoa clade. They likely do not possess vinculin proteins. Their metabolism relies on fermentative production of ATP as an adaptation to their low-oxygen environment.

<span class="mw-page-title-main">Podiata</span> Clade of shelled animals

Podiates are a proposed clade containing the Amorphea and the organisms now assigned to the clade CRuMs. Ancyromonadida does not appear to have emerged in this grouping. Sarcomastigota is a proposed subkingdom that includes all the podiates that are not animals or fungi. Sulcozoa is a proposed phylum within Sarcomastigota that does not include the phyla Amoebozoa (clade) and Choanozoa (paraphyletic), i.e. it includes the proposed subphyla Apusozoa and Varisulca

<span class="mw-page-title-main">Varisulca</span> Proposed phylum of protists

Varisulca was a proposed basal Podiate taxon. It encompassed several lineages of heterotrophic protists, most notably the ancyromonads (planomonads), collodictyonids (diphylleids), rigifilids and mantamonadids. Recent evidence suggests that the latter three are closely related to each other, forming a clade called CRuMs, but that this is unlikely to be specifically related to ancyromonads

<span class="mw-page-title-main">Cryptista</span> Phylum of algae

Cryptista is a clade of alga-like eukaryotes. It is most likely related to Archaeplastida which includes plants and many algae, within the larger group Diaphoretickes.

Mantamonads are a group of free-living heterotrophic flagellates that move primarily by gliding on surfaces. They are classified as one genus Mantamonas in the monotypic family Mantamonadidae, order Mantamonadida and class Glissodiscea. Previously, they were classified in Apusozoa as sister of the Apusmonadida on the basis of rRNA analyses. However, mantamonads are currently placed in CRuMs on the basis of phylogenomic analyses that identify their closest relatives as the Diphylleida and Rigifilida.

<span class="mw-page-title-main">CRuMs</span> Group of protists

CRuMs or Crumalia is a proposed clade of microbial eukaryotes, whose name is an acronym of the following constituent groups: i) collodictyonids also known as diphylleids, ii) rigifilids and iii) mantamonadids as sister of the Amorphea. It more or less supersedes Varisulca, as Ancyromonadida are inferred not to be specifically related to the orders Diphylleida/Collodictyonida, Rigifilida and Mantamonadida.

A supergroup, in evolutionary biology, is a large group of organisms that share one common ancestor and have important defining characteristics. It is an informal, mostly arbitrary rank in biological taxonomy that is often greater than phylum or kingdom, although some supergroups are also treated as phyla.

<span class="mw-page-title-main">Malawimonad</span> Order of flagellates

Malawimonads are a small group of microorganisms with a basal position in the evolutionary tree of eukaryotes, containing only three recognized species. They're considered part of a possibly paraphyletic group known as "Excavata".

<span class="mw-page-title-main">Evosea</span> Group of amoebae

Evosea is a diverse clade of amoeboid protists discovered through molecular analyses. Along with Tubulinea and Discosea, Evosea is one of the three major groups within Amoebozoa, an important clade of eukaryotic organisms. It contains unicellular organisms that display a wide variety of life cycles and cell shapes, including amoebae, flagellates and different kinds of slime molds.

References

  1. 1 2 Brown, M.W.; Sharpe, S.C.; Silberman, J.D.; Heiss, A.A.; Lang, B.F.; Simpson, A.G.B.; Roger, A.J. (2013). "Phylogenomics demonstrates that breviate flagellates are related to opisthokonts and apusomonads". Proceedings of the Royal Society B: Biological Sciences . 280 (1769): 20131755. doi: 10.1098/rspb.2013.1755 . JSTOR   43601549. OCLC   8093015610. PMC   3768317 . PMID   23986111. S2CID   19627175 .
  2. Eme, Laura; Sharpe, Susan C.; Brown, Matthew W.; Roger, Andrew J. (2014). "On the Age of Eukaryotes: Evaluating Evidence from Fossils and Molecular Clocks". Cold Spring Harbor Perspectives in Biology. 6 (8): a016139. doi:10.1101/cshperspect.a016139. ISSN   1943-0264. PMC   4107988 . PMID   25085908.
  3. Ruggiero, Michael A.; Gordon, Dennis P.; Orrell, Thomas M.; Bailly, Nicolas; Bourgoin, Thierry; Brusca, Richard C.; Cavalier-Smith, Thomas; Guiry, Michael D.; Kirk, Paul M. (2015-06-11). "Correction: A Higher Level Classification of All Living Organisms". PLOS ONE. 10 (6): e0130114. Bibcode:2015PLoSO..1030114R. doi: 10.1371/journal.pone.0130114 . ISSN   1932-6203. PMC   5159126 . PMID   26068874.
  4. Cavalier-Smith, Thomas; Fiore-Donno, Anna Maria; Chao, Ema; Kudryavtsev, Alexander; Berney, Cédric; Snell, Elizabeth A.; Lewis, Rhodri (2015-02-01). "Multigene phylogeny resolves deep branching of Amoebozoa". Molecular Phylogenetics and Evolution. 83: 293–304. doi: 10.1016/j.ympev.2014.08.011 . PMID   25150787.
  5. Cavalier-Smith T (2009). "Megaphylogeny, cell body plans, adaptive zones: causes and timing of eukaryote basal radiations". J. Eukaryot. Microbiol. 56 (1): 26–33. doi: 10.1111/j.1550-7408.2008.00373.x . PMID   19340985.
  6. 1 2 Brown, M.W.; Heiss, A.A.; Kamikawa, R.; Inagaki, Y.; Yabuki, A.; Tice, A.K.; Shiratori, T.; Ishida, K.-I.; Hashimoto, T.; Simpson, A.G.B.; Roger, A.J. (2018). "Phylogenomics Places Orphan Protistan Lineages in a Novel Eukaryotic Super-Group". Genome Biology and Evolution . 10 (2): 427–433. bioRxiv   10.1101/227884 . doi: 10.1093/gbe/evy014 . OCLC   7315371047. PMC   5793813 . PMID   29360967. S2CID   46757580 .
  7. Schön ME, Zlatogursky VV, Singh RP, et al. (2021). "Picozoa are archaeplastids without plastid". Nature Communications. 12 (1): 6651. bioRxiv   10.1101/2021.04.14.439778 . doi:10.1038/s41467-021-26918-0. PMC   8599508 . PMID   34789758. S2CID   233328713.
  8. Tikhonenkov DV, Mikhailov KV, Gawryluk RM, et al. (December 2022). "Microbial predators form a new supergroup of eukaryotes". Nature. 612 (7941): 714–719. Bibcode:2022Natur.612..714T. doi:10.1038/s41586-022-05511-5. PMID   36477531. S2CID   254436650.
  9. Burki, Fabien; Roger, Andrew J.; Brown, Matthew W.; Simpson, Alastair G.B. (2020). "The New Tree of Eukaryotes". Trends in Ecology & Evolution. 35 (1). Elsevier: 43–55. doi: 10.1016/j.tree.2019.08.008 . ISSN   0169-5347. PMID   31606140. S2CID   204545629.