A supergroup or super-group, in

systematics Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

, 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 Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, origin, evolution, and distribution of ...

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

that is often greater than

phylum In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead ...

or kingdom, although some supergroups are also treated as

phyla Phyla, the plural of ''phylum'', may refer to: * Phylum, a biological taxon between Kingdom and Class * by analogy, in linguistics, a large division of possibly related languages, or a major language family which is not subordinate to another Phy ...

Eukaryotic supergroups

Since the decade of the 2000s, the eukaryotic tree of life (abbreviated as eToL) has been divided into 5–8 major groupings called 'supergroups'. These groupings were established after the idea that only

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

groups should be accepted as ranks, as an alternative to the use of

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

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 ...

. In the early days of the eToL six traditional supergroups were considered:

Amoebozoa Amoebozoa is a major Taxonomy (biology), taxonomic group containing about 2,400 described species of Amoeba, amoeboid protists, often possessing blunt, fingerlike, Pseudopod#Morphology, lobose pseudopods and tubular mitochondrial cristae. In trad ...

, Opisthokonta, "

Excavata Excavata is an obsolete, extensive and diverse 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 ...

Archaeplastida The Archaeplastida (or kingdom Plantae '' sensu lato'' "in a broad sense"; pronounced ) are a major group of eukaryotes, comprising the photoautotrophic red algae (Rhodophyta), green algae, land plants, and the minor group glaucophytes. It als ...

, "

Chromalveolata Chromalveolata was a eukaryote supergroup present in a major classification of 2005, then regarded as one of the six major groups within the eukaryotes. It was a refinement of the kingdom Chromista, first proposed by Thomas Cavalier-Smith in 198 ...

" and

Rhizaria The Rhizaria are a diverse and species-rich clade of mostly unicellular eukaryotes. Except for the Chlorarachniophytes and three species in the genus '' Paulinella'' in the phylum Cercozoa, they are all non-photosynthetic, but many Foraminifera ...

. Since then, the eToL has been rearranged profoundly, and most of these groups were found as

or lacked defining morphological characteristics that unite their members, which makes the 'supergroup' label more arbitrary. Currently, the addition of many lineages of newly discovered

protist A protist ( ) or protoctist is any eukaryotic organism that is not an animal, land plant, or fungus. Protists do not form a natural group, or clade, but are a paraphyletic grouping of all descendants of the last eukaryotic common ancest ...

s (such as

Telonemia Telonemia is a phylum of microscopic eukaryotes commonly known as telonemids. They are unicellular free-living flagellates with a unique combination of Cell (biology), cell structures, including a highly complex cytoskeleton unseen in other eu ...

Picozoa Picozoa, Picobiliphyta, Picobiliphytes, or Biliphytes are protists of a phylum of marine unicellular heterotrophic eukaryotes with a size of less than about 3 micrometers. They were formerly treated as eukaryotic algae and the smallest member of ...

Hemimastigophora Hemimastigophora is a group of unicellular, single-celled eukaryotic organisms including the Spironematellidae, first identified in 1988, and the Paramastigidae. Over the next 30 years, different authors proposed placing these organisms in v ...

Rigifilida Rigifilida is a clade of non-ciliate phagotrophic eukaryotes. It consists of two genera: '' Micronuclearia'' and '' Rigifila''. Characteristics Cells of rigifilids are covered with either a single or a double-layered submembrane pellicular lam ...

...) and the use of

phylogenomic Phylogenomics is the intersection of the fields of evolution and genomics. The term has been used in multiple ways to refer to analysis that involves genome data and evolutionary reconstructions. It is a group of techniques within the larger fields ...

analyses have brought a new, more accurate supergroup model. These are the current supergroups of eukaryotes: *

TSAR Tsar (; also spelled ''czar'', ''tzar'', or ''csar''; ; ; sr-Cyrl-Latn, цар, car) is a title historically used by Slavic monarchs. The term is derived from the Latin word '' caesar'', which was intended to mean ''emperor'' in the Euro ...

, constituted by

and the SAR

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

(

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 ...

, Alveolata and

). It is estimated to occupy up to half of all eukaryotic diversity, since it includes multiple major groups such as

diatoms A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's B ...

dinoflagellates The Dinoflagellates (), also called Dinophytes, are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered protists. Dinoflagellates are mostly marine plankton, but they are also commo ...

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), '' Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

ciliate The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to flagellum, eukaryotic flagella, but are in general shorter and present in much larger numbers, with a ...

foraminifera Foraminifera ( ; Latin for "hole bearers"; informally called "forams") are unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell bio ...

ns,

radiolaria The Radiolaria, also called Radiozoa, are unicellular eukaryotes of diameter 0.1–0.2 mm that produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ect ...

ns, and the

apicomplexa The Apicomplexa (also called Apicomplexia; single: apicomplexan) are organisms of a large phylum of mainly parasitic alveolates. Most possess a unique form of organelle structure that comprises a type of non-photosynthetic plastid called an ap ...

n and

oomycete 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 ...

parasites. It essentially contains the majority of "

". *

Haptista Haptista is a proposed group of protists made up of centrohelids and haptophytes. Phylogenomic studies indicate that Haptista, together with ''Ancoracysta twista'', forms a sister clade to the SAR supergroup#Internal phylogeny, TSAR Supergroup (b ...

(ranked as a phylum), previously in "

", comprising the

haptophyte The haptophytes, classified either as the Haptophyta, Haptophytina or Prymnesiophyta (named for '' Prymnesium''), are a clade of algae. The names Haptophyceae or Prymnesiophyceae are sometimes used instead. This ending implies classification at ...

algae and

centrohelid The centrohelids or centroheliozoa are a large group of heliozoan protists. They include both mobile and sessile forms, found in freshwater and marine environments, especially at some depth. Characteristics Individuals are unicellular and spher ...

s. *

Cryptista 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. Other characteristic features of cryptophyte mtDNAs include large syntenic ...

(ranked as a phylum), previously in "

", comprising the

cryptomonad The cryptomonads (or cryptophytes) are a superclass of algae, most of which have plastids. They are traditionally considered a division of algae among phycologists, under the name of Cryptophyta. They are common in freshwater, and also occur ...

katablepharid The kathablepharids or katablepharids () are a group of heterotrophic flagellates closely related to cryptomonads. First described by Heinrich Leonhards Skuja in 1939, kathablepharids were named after the genus '' Kathablepharis''. This genus is ...

s and the enigmatic ''

Palpitomonas ''Palpitomonas'' is a genus of biflagellated protists within the phylum Cryptista'','' a clade of basal eukaryotes. This genus is especially significant for understanding the early evolution of mitochondria, flagella, and the broader cryptist l ...

''. *

(also treated as a kingdom), constituted by the lineages that acquired

chloroplasts A chloroplast () is a type of membrane-bound organelle, organelle known as a plastid that conducts photosynthesis mostly in plant cell, plant and algae, algal cells. Chloroplasts have a high concentration of chlorophyll pigments which captur ...

through primary endosymbiosis:

Chloroplastida Viridiplantae (; kingdom Plantae '' sensu stricto'') is a clade of around 450,000–500,000 species of eukaryotic organisms, most of which obtain their energy by photosynthesis. The green plants are chloroplast-bearing autotrophs that play impo ...

(

green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...

and

land plants The embryophytes () are a clade of plants, also known as Embryophyta (Plantae ''sensu strictissimo'') () or land plants. They are the most familiar group of photoautotrophs that make up the vegetation on Earth's dry lands and wetlands. Embryophy ...

Rhodophyta Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest phyla of algae, containing over 7,000 recognized species within over 900 genera amidst ongoing taxonomic revisions. ...

Glaucophyta The glaucophytes, also known as glaucocystophytes or glaucocystids, are a small group of unicellular algae found in freshwater and moist terrestrial environments, less common today than they were during the Proterozoic. The stated number of spec ...

and '' Rhodelphis''. *

Amorphea Amorphea is a taxonomic supergroup that includes the basal Amoebozoa and Obazoa. That latter contains the Opisthokonta, which includes the fungi, animals and the choanoflagellates. The taxonomic affinities of the members of this clade were ...

, composed by the

and the Opisthokonta (

animal Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...

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 mushrooms. These organisms are classified as one ...

and related protists). They're related to the

breviate 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 ...

s and the

apusomonad The apusomonads (family Apusomonadidae) 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 ...

s, and together form the clade

Obazoa 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 Apusomonadidae, the group's three constituent clades. Determining the placement of Bre ...

. *

CRuMs CRuMs is a clade of microbial eukaryotes, whose name is an acronym of the following constituent groups: i) Diphylleids, ii) rigifilids and iii) mantamonads as sister of the Amorphea. A new CRuMs order Glissandrida was proposed in 2025 to pla ...

, (ranked as a phylum) composed by the free-living protozoan groups

Collodictyonidae Collodictyonidae (also Diphylleidae) is a group of aquatic, unicellular eukaryotic organisms with two to four terminal flagella. They feed by phagocytosis, ingesting other unicellular organisms like algae and bacteria Bacteria (; : bac ...

and ''

Mantamonas Mantamonads are a group of free-living heterotrophic flagellates that move primarily by gliding on surfaces (rather than swimming). They are classified as one genus ''Mantamonas'' in the monotypic family Mantamonadidae, order Mantamonadida, clas ...

''. *

Discoba Excavata is an obsolete, extensive and diverse Paraphyly, paraphyletic group of unicellular Eukaryote, Eukaryota. The group was first suggested by Simpson and Patterson in 1999 and the name latinized and assigned a rank by Thomas Cavalier-Smit ...

, constituted by Discicristata (

Euglenozoa Euglenozoa are a large group of flagellate Discoba. They include a variety of common free-living species, as well as a few important parasites, some of which infect humans. Euglenozoa are represented by four major groups, ''i.e.,'' Kinetoplastea, ...

and

Heterolobosea Heterolobosea are a class of Percolozoa. The only member of this class that is infectious to humans is '' Naegleria fowleri'', the causative agent of the often fatal disease amoebic meningitis. Typically, their life cycle alternates between fl ...

), Jakobida and '' Tsukubamonas''. It is the biggest remaining clade of the "

". * Metamonada, (ranked as a phylum) previously part of the " Excavates", entirely containing

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: *Adhesive#Anaerobic, Anaerobic ad ...

protists. *

, (ranked as a phylum) previously an orphan clade but recently brought into

Diaphoretickes Diaphoretickes is a major group of eukaryote, eukaryotic organisms spanning over 400,000 species. The majority of the earth's biomass that carries out photosynthesis belongs to Diaphoretickes. In older classification systems, members of the Diaph ...

. *

Provora Provora is a supergroup of eukaryotes made up of predatory microbes, whose name implies something such as "protists devouring voraciously". It was reported that ten strains were isolated and cultured in 2022. They are predators of other microor ...

, the most recent supergroup, containing the previously orphan '' Ancoracysta''. Many orphan groups of free-living protozoa remain left behind, unable to be added to a supergroup, such as:

(possibly belongs to

with limited certainty),

Malawimonadida Malawimonads (order Malawimonadida) 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 paraphyletic group known as "Excavata". ...

(thought to be related to Metamonada),

Ancyromonadida Ancyromonadida or Planomonadida is a small group of biflagellated eukaryotes found in the soil and in aquatic habitats, where they feed on bacteria.Cavalier-Smith, T. (2013)Early evolution of eukaryote feeding modes, cell structural diversity, a ...

Breviatea 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 ...

Apusomonadida The apusomonads (family Apusomonadidae) 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 ...

, etc. A possible modern topology of the eToL would be the following (supergroups labeled in bold):

Prokaryotic supergroups

The term 'supergroup' is used in

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

studies of bacteria, in a smaller sense than within eukaryotes. As of 2021, it is very commonly used for naming clades within the genus ''

Wolbachia ''Wolbachia'' is a genus of gram-negative bacteria infecting many species of arthropods and filarial nematodes. The symbiotic relationship ranges from parasitism to obligate mutualism. It is one of the most common parasitic microbes of arthrop ...

''.

References

{{Reflist, refs= {{cite journal, vauthors=Burki F, Roger AJ, Brown MW, ((Simpson AGB)), title=The New Tree of Eukaryotes, journal=Trends Ecol Evol, date=January 2020, volume=35, issue=1, pages=43–55, doi=10.1016/j.tree.2019.08.008, pmid=31606140, doi-access=free, url=https://uu.diva-portal.org/smash/get/diva2:1387649/FULLTEXT01 {{cite journal , title=The real 'kingdoms' of eukaryotes , last1=Simpson , first1=Alastair G.B. , last2=Roger , first2=Andrew J. , journal=

Current Biology ''Current Biology'' is a biweekly peer-reviewed scientific journal that covers all areas of biology, especially molecular biology, cell biology, genetics, neurobiology, ecology, and evolutionary biology. The journal includes research artic ...

, volume=14 , issue=17 , pages=R693–R696 , doi=10.1016/j.cub.2004.08.038 , pmid=15341755, year=2004 , s2cid=207051421 , doi-access=free {{cite journal, vauthors=((Strassert JFH)), Jamy M, Mylnikov AP, Tikhonenkov DV, Burki F, title=New Phylogenomic Analysis of the Enigmatic Phylum Telonemia Further Resolves the Eukaryote Tree of Life, journal=Molecular Biology and Evolution, volume=36, issue=4, date=April 2019, pages=757–765, doi=10.1093/molbev/msz012, doi-access=free, pmc=6844682 {{cite journal , title=Microbial predators form a new supergroup of eukaryotes , year=2022 , last1=Tikhonenkov , first1=Denis V. , last2=Mikhailov , first2=Kirill V. , last3=Gawryluk , first3=Ryan M. R. , last4=Belyaev , first4=Artem O. , last5=Mathur , first5=Varsha , last6=Karpov , first6=Sergey A. , last7=Zagumyonnyi , first7=Dmitry G. , last8=Borodina , first8=Anastasia S. , last9=Prokina , first9=Kristina I. , last10=Mylnikov , first10=Alexander P. , last11=Aleoshin , first11=Vladimir V. , last12=Keeling , first12=Patrick J. , journal=Nature , doi=10.1038/s41586-022-05511-5 , pmid=36477531 {{citation, vauthors=Brown MW, etal, title=Phylogenomics Places Orphan Protistan Lineages in a Novel Eukaryotic Super-Group, journal=Genome Biology and Evolution, volume=10, issue=2, pages=427-433, doi=10.1093/gbe/evy014, date=2018, doi-access=free, pmc=5793813 {{cite journal, first1=Edyta, last1=Konecka, first2=Ziemowit, last2=Olszanowski, title=Wolbachia supergroup E found in Hypochthonius rufulus (Acari: Oribatida) in Poland, journal=Infection, Genetics and Evolution, volume=91, date=2021, number=104829, issn=1567-1348, doi=10.1016/j.meegid.2021.104829, doi-access=free {{cite journal, vauthors=Covacin C, Barker SC, title=Supergroup F Wolbachia bacteria parasitise lice (Insecta: Phthiraptera), journal=Parasitol Res, volume=100, pages=479–485, date=2007, doi=10.1007/s00436-006-0309-6 {{cite journal, vauthors=Baldo L, Werren JH, title=Revisiting Wolbachia Supergroup Typing Based on WSP: Spurious Lineages and Discordance with MLST, journal=Curr Microbiol, volume=55, pages=81–87, date=2007, doi=10.1007/s00284-007-0055-8 Eukaryote taxa