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 and class Glissodiscea.[2] Previously, they were classified in Apusozoa as sister of the Apusomonadida on the basis of rRNA analyses.[1][4] However, mantamonads are currently placed in CRuMs on the basis of phylogenomic analyses that identify their closest relatives as the Diphylleida and Rigifilida.[5][6]

Mantamonas
Scientific classification Edit this classification
Domain: Eukaryota
Clade: Opimoda
Clade: CRuMs
Class: Glissodiscea
Cavalier-Smith 2013 emend. 2021[2]
Order: Mantamonadida
Cavalier-Smith 2011[1]
Family: Mantamonadidae
Cavalier-Smith 2011[1]
Genus: Mantamonas
Cavalier-Smith & Glücksman 2011[1]
Type species
Mantamonas plastica
Glücksman & Cavalier-Smith 2011[1]
Species
Diversity
3 species[3]

Morphology

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Mantamonas are heterotrophic unicellular protists. Their cells are flattened, relatively plastic and asymmetric. They have one thin anterior flagellum and one conspicuous posterior flagellum, on which they glide. The cells have a right hump, likely caused by the nucleus, and a blunt projection on the left side. They are typically 2 μm thick,[1] 5 μm long and 5 μm wide, but vary in size and shape depending on their growth phase and the bacterial density in the medium.[3] When wide-shaped, they present lateral "wings" that resemble the fins of a manta ray (hence the name Mantamonas).[3]

Ecology

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Mantamonas are marine gliding heterotrophic flagellates. M. plastica was isolated from marine sediments, while M. vickermani was isolated from marine lagoon sediments. M. sphyraenae was obtained from the skin surface of a barracuda, suggesting that it could be an epizootic species.[3]

Evolution

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When discovered in 2011, a phylogenetic analysis based on 28S and 18S rRNA recovered Mantamonas as a lineage closely related to Planomonadida and Apusomonadida, within the paraphyletic Apusozoa.[1] Later in 2018, a phylogenomic analysis recovered Mantamonas as the sister group of a clade comprising Collodictyonidae and Rigifilida. Together, the three groups compose the CRuMs clade, which is the sister group to Amorphea (Amoebozoa + Obazoa) in a clade known as Podiata.[6]

Eukaryota

Diaphoretickes

Discoba

Metamonada Cavalier-Smith 1987 emend. Cavalier-Smith 2003

Ancyromonadida Cavalier-Smith 1998 emend. Atkins 2000

Malawimonadea Cavalier-Smith 2003

Podiata
Amorphea

Amoebozoa Lühe 1913 emend. Cavalier-Smith 1998

Obazoa

Breviatea Cavalier-Smith 2004

Apusomonadida Karpov & Mylnikov 1989

Opisthokonta

CRuMs

Rigifilida Karpov & Mylnikov 1989

Diphylleida Cavalier-Smith 1993

Species

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There are currently three species of Mantamonas.[3]

References

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  1. ^ a b c d e f g h Glücksman, Edvard; Snell, Elizabeth A.; Berney, Cédric; Chao, Ema E.; Bass, David; Cavalier-Smith, Thomas (September 2010). "The Novel Marine Gliding Zooflagellate Genus Mantamonas (Mantamonadida ord. n.: Apusozoa)". Protist. 162 (2): 207–221. doi:10.1016/j.protis.2010.06.004. PMID 20884290.
  2. ^ a b Cavalier-Smith, Thomas (May 2022). "Ciliary transition zone evolution and the root of the eukaryote tree: implications for opisthokont origin and classification of kingdoms Protozoa, Plantae, and Fungi". Protoplasma. 259 (3): 487–593. doi:10.1007/s00709-021-01665-7. PMC 9010356. PMID 34940909.
  3. ^ a b c d e Blaz, Jazmin; Galindo, Luis Javier; Heiss, Aaron A.; Kaur, Harpreet; Torruella, Guifré; Yang, Ashley; Thompson, L. Alexa; Filbert, Alexander; Warring, Sally; Narechania, Apurva; Shiratori, Takashi; Ishida, Ken-ichiro; Dacks, Joel B.; López-García, Purificación; Moreira, David; Kim, Eunsoo; Eme, Laura (January 2021). "High quality genome and transcriptome data for two new species of Mantamonas, a deep-branching eukaryote clade". bioRxiv. doi:10.1101/2023.01.20.524885.
  4. ^ Orr, Russell J. S.; Zhao, Sen; Klaveness, Dag; Yabuki, Akinori; Ikeda, Keiji; Makoto, Watanabe M.; Shalchian-Tabrizi, Kamran (2017-10-08). "Enigmatic Diphyllatea eukaryotes: Culturing and targeted PacBio RS amplicon sequencing reveals a higher order taxonomic diversity and global distribution". bioRxiv 10.1101/199125.
  5. ^ Cavalier-Smith, Thomas; Chao, Ema E.; Snell, Elizabeth A.; Berney, Cédric; Fiore-Donno, Anna Maria; Lewis, Rhodri (2014). "Multigene eukaryote phylogeny reveals the likely protozoan ancestors of opisthokonts (animals, fungi, choanozoans) and Amoebozoa". Molecular Phylogenetics and Evolution. 81: 71–85. doi:10.1016/j.ympev.2014.08.012. PMID 25152275.
  6. ^ a b Brown, Matthew W; Heiss, Aaron A; Kamikawa, Ryoma; Inagaki, Yuji; Yabuki, Akinori; Tice, Alexander K; Shiratori, Takashi; Ishida, Ken-Ichiro; Hashimoto, Tetsuo (January 2018). "Phylogenomics Places Orphan Protistan Lineages in a Novel Eukaryotic Super-Group". Genome Biology and Evolution. 10 (2): 427–433. doi:10.1093/gbe/evy014. ISSN 1759-6653. PMC 5793813. PMID 29360967.