Provora is a supergroup of

eukaryotes The eukaryotes ( ) constitute the domain of Eukaryota or Eukarya, organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of ...

made up of

predatory Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill ...

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 microorganisms. Their discovery was very delayed, compared to other microorganisms in their environments, due to their rarity. Their

18S ribosomal RNA 18S ribosomal RNA (abbreviated 18S rRNA) is a part of the ribosomal RNA in eukaryotes. It is a component of the Eukaryotic small ribosomal subunit (40S) and the cytosolic homologue of both the 12S ribosomal RNA, 12S rRNA in mitochondria and the 1 ...

is very different from that of other eukaryotes consistent with their being a lineage without known close relatives; this was confirmed by phylogenomic analyses of datasets of several hundred proteins, so they were taxonomically placed in a separate supergroup.

Evolution

External relationships

The supergroup Provora is composed of microbes that form an ancient lineage of

eukaryote The eukaryotes ( ) constitute the Domain (biology), domain of Eukaryota or Eukarya, organisms whose Cell (biology), cells have a membrane-bound cell nucleus, nucleus. All animals, plants, Fungus, fungi, seaweeds, and many unicellular organisms ...

s. The initial

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

recovered a position within the larger supergroup

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 ...

, particularly as sister to the

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 ...

groups

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 ...

and

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 ...

. However, a 2024 phylogenomic analysis recovered Provora as part of a novel lineage of eukaryotes, specifically as the sister group to a clade containing

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 ...

and the species '' Meteora sporadica''. Either position is reflected in the biology of Provora: their extrusomes are similar to those found in Hemimastigophora, while other cellular features most closely resemble those found in TSAR and Haptista, such as flagellar vanes, the architecture of the flagellar apparatus, and the presence of cortical alveoli below the cell membrane. The following cladogram represents the two alternative evolutionary positions:

Internal relationships

The phylogenetic relationships between the eight described species of Provora is the following:

References

{{Taxonbar, from=Q115803353 Diaphoretickes taxa Protist taxa