Provora
Provora is a proposed supergroup of eukaryotes made up of predatory microbes, "devouring voracious protists". 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 is very different from that of other eukaryotes consistent with their being a lineage without close relatives; this was confirmed by phylogenomic analyses of datasets of several hundred proteins, so they were taxonomically placed in a separate supergroup.[1][2] EvolutionExternal relationshipsThe supergroup Provora is composed of microbes that form an ancient lineage of eukaryotes. The initial phylogenetic analyses recovered a position within the larger supergroup Diaphoretickes, particularly as sister to the protist groups TSAR and Haptista.[1] 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 and the species Meteora sporadica.[3] 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.[4] The following cladogram represents the two alternative evolutionary positions: Internal relationshipsThe phylogenetic relationships between the eight described species of Provora is the following:[1][4]
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